Two women are accused of poisoning their own children at the same hospital. They say it tore their lives apart.
It was springtime in 2014 in a regional town just outside Sydney when Alison* noticed her son was unsteady on his feet.
He'd had headaches and been vomiting for a few days, but a local GP told her it was just a bug.
Then, he asked her an odd question that made her worried: "Mum, why are you cooking scrambled eggs in my head?"
Soon after, Liam* collapsed. As Alison raced down the highway to the local hospital, his face began to turn grey.
A trained nurse, she slammed an EpiPen into his thigh. As she pulled up at the hospital, a security guard scooped the boy into his arms.
Doctors didn't know what was happening. Liam had brittle asthma, a particularly intense form of the condition. They thought an asthma attack might have sent him into cardiac arrest.
Soon, a helicopter whisked Liam and Alison to Westmead Children's Hospital, in the geographic heart of Sydney, so he could be treated in intensive care.
While Alison and Liam entered together, they would leave separately. It was the beginning of a story that would see Alison lose her home, her children and her sanity, until she sat in a criminal court accused of an almost unfathomable crime.
The blood sample
Down at Westmead, doctors performed a spinal tap to reduce some of the pressure in Liam's head. He responded quickly to treatment for his asthma. The crisis was over, but the hospital stay was just beginning.
Alison remembers doctors telling her they thought the high doses of steroids her son was on to treat his asthma had caused a build-up of pressure in his brain. It would be a slow process, but they wanted to wean him off them. She agreed.
But it wasn't straightforward. Liam would start feeling better but then rapidly decline, getting fevers with a soaring heart rate and plunging blood pressure. Twice, he was sent back to intensive care.
A month into his admission, Liam was feeling better, well enough to be playing video games in his bed on the ward.
He was playing with another child when a woman entered the room.
She said she was a child protection worker with the NSW agency now called the Department of Communities and Justice. "You need to come with me," she told Alison.
Exhausted and dishevelled from the month-long hospital stay, Alison followed her to a small room a few levels up. Another woman introduced herself as a senior constable with NSW Police.
For just over an hour, the pair probed Alison on her life: her kids' relationship with their father, her employment history, her son's medical history, and their stay at the hospital.
Tape of this questioning would later be played in the District Court.
Alison voiced her frustration with the difficulties of weaning her son off steroids. She'd threatened to take him home that week.
And then, she added, there's the E. coli.
Earlier, she'd been told a blood culture taken from her son had grown bacteria found in the human gut — a sign that he had an infection or his blood culture had been contaminated.
"It's like a vicious cycle in here. You come in for one thing, you pick up bugs, the medications do something wrong to you," she groused.
The interview ended. An hour later, they told her Liam was being taken into the care of the state.
Alison asked to see the doctors' report this decision was based on but was denied: instead, it was read to her.
Over the six minutes it took the child protection worker to read those 800 words, it slowly became clear what, or rather who, doctors wanted to protect Liam from.
An infectious diseases specialist thought the most likely explanation for Liam's fevers and the E. coli in his blood culture was that faecal or decaying material — poo — had been injected into his IV line.
And it was pretty clear to everyone who the main suspect was — it was Alison.
Alison was indignant. She argued she was a good mum and there was no proof she'd done anything wrong.
The child protection worker didn't budge: "A professor is telling us it's a life-threatening situation, and we can't ignore that."
Over the course of the 20-minute meeting, Alison kept trying to argue back. "I appreciate you guys want to protect a child. That's fine, but not a child who's not at risk."
"He is at risk," the police officer replied.
"Not from me, he's not," she said.
They searched her bag, then security walked Alison directly out of the hospital building.
It was nearly 10pm, her phone was almost out of battery, and she had nowhere to go. She was not allowed to return home to her other children.
When authorities interviewed Liam that night, he asked to see his mum six times. They reassured him he'd see her soon. But they wouldn't lay eyes on each other for another seven months.
A relative in Sydney came and picked Alison up.
"I just cried all night, I couldn't sleep," Alison says. "And that's where my — our — whole lives got destroyed."
The professor
When Alison had met the doctor who wrote that report the week before, he was just another man in a white coat involved in her son's care. She didn't know he would change the course of her life.
Professor David Isaacs was a paediatrician and infectious diseases specialist with more than 30 years' experience, a clinical professor at the University of Sydney. He was well known and well respected: he'd advocated publicly for better treatment of young refugees after working at the Nauru offshore immigration detention centre.
Liam's doctors at Westmead had asked Professor Isaacs to help them figure out why Liam kept experiencing the strange fevers. When he'd spent 10 minutes talking with Alison, she'd told him her ex-husband had moved out and she was struggling as a single mum with her four young kids.
Then Isaacs had learned of the positive blood culture. He was worried. He couldn't find a medical explanation for the E. coli, like an infection, and the antibiotics Liam was taking should have dealt with it.
He would later tell a court he discussed the blood test result with colleagues, including the respiratory physician weaning Liam off the steroids.
Professor Isaacs grew to suspect someone was deliberately injecting contaminants into Liam's blood.
Against the wishes of the respiratory doctor, Professor Isaacs picked up the phone to the hospital's child protection unit. As a doctor, he had a legal obligation to sound the alarm, he told his colleague.
At a meeting of doctors, caseworkers and police, Professor Isaacs argued that Liam would die if this was allowed to continue. The meeting was also told nurses had overheard Liam asking his mother what she was putting in his cannula and complaining that she was poisoning him.
Alison was separated from her son, and her other kids, the following day.
The controversial disorder
A mother injecting her own son with poo sounds like a grotesque nightmare, but Professor Isaacs knew that it wasn't unthinkable. Injection with a contaminant is the rarest, darkest end of a spectrum of behaviour that was once called Munchausen syndrome by proxy, or Munchausen's for short.
The term was born in a 1977 article in The Lancet. The author was British paediatrician Sir Roy Meadow, who described how some children's mysterious illnesses were actually caused by their mother. Meadow later speculated that the women were trying to use their sick child to capture doctors' attention.
The term caught on, and panic only grew when another British paediatrician covertly captured horrifying videotape of mothers suffocating their kids in hospital when they weren't being watched.
A health worker herself, Alison immediately understood what she was being accused of. Her son hadn't had a temperature in days, she told the investigators. She asked: "If I was some crazy Munchie, wouldn't I be injecting him every day?"
Around the 2000s, the Munchausen's label came under sharper scrutiny. Critics pointed out that the syndrome was imprecise, its empirical foundations shaky, and that it had never been recognised as a mental disorder.
A profile of the Munchausen's Mum had developed in the literature. But it shared many of the traits of good, harmless parents: perpetrators never left their child's bedside, were prone to doctor-shopping, and had strong medical knowledge (many were healthcare workers themselves).
Though there were disagreements about what to call it and how to understand it, nobody disputed that sometimes mothers did invent illnesses or make their children sick.
In Australia, mothers have been convicted for poisoning their children with cancer treatment drugs and epilepsy medication — and, prior to Alison being accused, at least one mother had already been convicted of injecting her child with excrement.
A lot of the children in cases like these have existing underlying health issues. Some psychiatrists say the behaviour can begin with a desire to get the attention of doctors — a sort of disturbing cry for help.
Today, "factitious disorder imposed on another" is a recognised psychiatric disorder, though Australian paediatricians prefer to talk about "fabricated or induced illness by a carer", shifting attention from the caregiver's personality and motivations to the impacts of their behaviour on the child.
Whatever its name, it is "arguably the most confronting condition a paediatrician ever has to manage", Professor Isaacs wrote in a 2015 journal article. In fact, he wrote, it's so confronting that some doctors can't see it and others fail to do anything even when they suspect it. He wrote: "In the last 25 years, at least three children died at the hands of their mother in our tertiary children's hospital, as good doctors failed to act on their suspicions."
Professor Isaacs urged his colleagues to notify authorities — even where they fear they don't have enough proof. "Paediatricians should know that the Children's Court will act to protect children on a lesser level of proof than is needed for a prosecution in the criminal court," he wrote.
"The main consideration should be the danger of harm, not the level of evidence."
But what if the doctors get it wrong?
Helen Hayward-Brown, a medical anthropologist, claims this happens regularly. Since she started investigating false accusations of Munchausen syndrome by proxy as part of a PhD in the 1990s, she claims she's heard from more than 100 women in Australia and New Zealand who say they've been falsely accused of making their children sick, including both of the women in this story.
Hearing their stories motivated her to become a kind of activist on the issue. Her husband retrained as a lawyer to assist women in this position (including, at one point, one of the women in this story).
Dr Hayward-Brown says often upon close examination the medical evidence reveals something else is going on — perhaps test results have been overlooked, the wrong medication has been administered, or the child has a rare medical condition that's been misunderstood.
Though most experts agree that mothers very rarely make their children sick, there's disagreement about exactly how prevalent it is, or how many women are falsely accused. This is part of the problem, according to University of North Carolina law professor Maxine Eichner, who's criticised the proliferation of so-called medical child abuse claims in the US.
"[Doctors] just don't have that feedback process for Munchausen syndrome by proxy," she says. "That means … they don't ever get to correct their diagnostic criteria and figure out how well they're doing."
While the old profile of the Munchausen's Mum has been roundly criticised as a useless diagnostic tool, the medical literature still lists red flags that suggest symptoms might be induced. These include women who elicit public sympathy, challenge doctors, refuse to allow their kids to be seen alone, plus nurses and those with strong medical knowledge and opinions.
But people with these traits are more often just mothers of genuinely ill children, Eichner says, and a false accusation can be devastating to a child and mother.
When Alison was marched out of Westmead, her life began to unravel. Three months later, and again the following year, the Children's Court ruled she could not have her children back. A psychologist told the court Alison suffered from depression and anxiety and her parenting style involved managing by crisis. The judge found that the kids were safe and thriving under their father's care — including Liam, who hadn't been hospitalised since that stay in Westmead.
The judge also found that faecal matter had been introduced into her son's bloodstream, and Alison had the opportunity to do it as she kept vigil by his bedside in the hospital.
Police went to court to get an AVO to protect her kids.
Then in June 2017, almost three years after the helicopter to Westmead, things got even worse. Police arrested and charged her with a crime, alleging she'd threatened her son's life by poisoning him. If found guilty, she faced up to 10 years in jail.
Awaiting trial, her mental health collapsed.
"Gradually, your friends stop calling and nobody calls anymore, and you get even more alone," she says.
"Then I just stopped being able to function, like I couldn't get out of bed or eat or have a shower."
Alison attempted suicide and ended up in intensive care.
She was an in-patient at a psychiatric hospital, and later was treated with electro-convulsive therapy. She says it caused her to lose several teeth and eroded her memory.
"It not only takes away the bad memories, it takes away the good memories," she says.
Tara and Katie
One day, in the midst of all of this, Alison got a call from another mother, who was in a strangely similar situation.
In March 2015, five months after Alison was escorted from the hospital, Tara*'s nine-year-old daughter Katie* was admitted to the same hospital.
Katie had been in and out of hospital since she was a baby. She had a rare genetic disorder, inherited from her father Thomas*, that left her with a weak immune system. Katie had struggled with recurrent diarrhoea and repeated urinary tract infections that doctors couldn't explain.
Tara had quit her job as a nurse and midwife when Katie was little to care for her, and she often shared her experiences as a mother of a chronically ill child on her website and social media. She says it was a way to be part of a community and abate her loneliness as she sat with her daughter in the hospital.
Tara and Katie found support in their local community too, with the high school running an annual fundraising day for Katie. Both sometimes appeared in the media to raise awareness about health issues.
That March, Katie had been admitted to a regional hospital closer to the rural town where the family lived, but they'd sent her on to Westmead in Sydney when she suffered renal failure.
One Monday night two weeks later, just before 10:30pm, two women came to the ward. "Don't make a scene in front of your daughter," Tara remembers them saying. Tara reassured Katie she'd be back, then followed them out of the room.
Blood taken from her daughter's central line had grown five strange organisms. The doctors believed it was no accident. They thought she'd injected her own daughter with urine.
It turned out doctors at the regional hospital Katie had been transferred from had also harboured suspicions. They thought Katie's chronic diarrhoea was caused by someone giving her laxatives.
At a meeting of doctors from the two hospitals earlier that day, doctors had discussed their fears with child protection authorities and police. Though he wasn't the one who initially sounded the alarm, and wasn't closely involved in Katie's care, one of the doctors who said she was in imminent danger was Professor Isaacs, the same doctor who had raised the alarm about Alison and her son, Liam.
Tara was taken to the local police station, where she agreed to be interviewed without a lawyer. They searched her handbag and found five syringes and urine sample pots. She told police she'd scooped them into her purse when the family had rushed from the regional hospital down to Westmead. As a former nurse and midwife, she was hands on with her daughter's care. The syringes weren't needles, they were plastic syringes for measuring liquid. She said she kept these to use for her daughter's painkillers and other oral medicines, and she said she had urine pots because she was often asked to collect her daughter's urine samples.
Tara was not under arrest, and the interview with the police was voluntary.
"I thought I would just go in and tell them the truth, tell them my side of the story, and they would see that the accusation was wrong and I was just a mum trying to look after my daughter," she says.
"But that's not what happened at all."
The removal
After she'd been confronted by police, Tara sent someone a text message: "They say that the evidence is damning and it is."
"I felt that it was going to be very one-sided, that they had made a decision about me," she explains. "Having been on the medical side, doctors and nurses are very good at twisting things to protect themselves. That was my feeling: they had culminated what they saw as evidence to use against me in a specific way."
Tara was interviewed by police from just after midnight until their computer systems went down at around 2am.
Then, she was released, and told she wasn't allowed to see her children.
Just before dawn, a hint of sunrise in the dark sky, Thomas met her at the carpark outside Westmead where the police had dropped her with instructions that she couldn't go back inside.
He'd received a panicked phone call from Tara in the night and urgently arranged for someone else to watch the kids.
"The fact that all this had happened through the night … it was an incredibly strange experience, and a very distressing one," he says.
He asked Tara a question. "He asked me, 'Did you hurt her?'" Tara recalls.
"I said 'No.' And he said, 'I believe you.'"
But when Thomas told child protection workers his wife was innocent, he also became the target of their concerns. "Their next move was to tell me that because I couldn't see that my wife had harmed our daughter, then I was not a suitable person to protect our child," he says.
"And now they were going to remove her from my care as well."
Katie was discharged from the hospital into foster care three weeks later.
She's now 16 and, for the first time, is ready to talk publicly about what she went through.
"The main thing I remember is when I was alone in there after Mum and I had been separated," she says about her stay at Westmead in 2015. Their relationship had been strong; they told each other everything.
"I didn't get told why it was happening. I just kind of woke up and she wasn't there," she says.
She started to suspect something wasn't right when she was told she couldn't call Tara. And when police and child protection authorities asked her whether she'd ever seen her mother giving her something she shouldn't, her suspicion grew. Katie told the authorities she'd never seen her mum do anything wrong, and that she was pretty cluey about what medicines she had to be taking and what all the medical equipment was for.
"I was confused, but I was also pretty angry that no one was telling me what was going on, and also that they just kind of weren't listening either," she remembers.
Katie wasn't allowed to see her mother at all — police applied for an apprehended domestic violence order on her behalf. Going into foster care meant she was separated from her brothers and sisters too.
The evidence
A few months later, police laid three criminal charges against Tara — two for the laxative allegations and one for the allegation she'd injected urine mixed with saliva into her daughter's central line at Westmead. Her other kids were removed from her as well.
Tara moved out of the family home to her mother's place so the rest of the family — bar Katie — could stay together. When the removal was reviewed by the Children's Court in 2016, Tara didn't fight the case lest it prejudice her criminal trial. The decision that Katie was at risk and couldn't be in the family's care was upheld. The judge found that it was probable that Tara had been the one administering laxatives to Katie, and/or contaminating her central line.
Nearly five years after the family was separated from Katie, the case finally made its way to the District Court in February 2020.
The prosecution's case was "entirely circumstantial", says Tara's defence lawyer, Mark Ramsland. "There was no direct evidence that she'd done anything wrong."
Prosecutors argued the unusual combination of fungi, and the timing of the positive test soon after her line had been changed, suggested they'd been deliberately introduced.
Then, there was the watery diarrhoea. Katie's gastroenterologist said he'd never been able to find a cause for it and it didn't seem connected to her underlying condition. A process of elimination, and a suspicious pigmentation of Katie's colon, led him to believe it was being induced.
The prosecution also argued that Katie's health had rapidly improved after she was separated from her mother, and that the mysterious infections, episodes of renal failure and diarrhoea had slowed essentially to a halt.
But cracks soon began to appear in the prosecution's case.
Asked why he hadn't reported his suspicions to child protection authorities beyond his hospital, the gastroenterologist said he hadn't thought Katie was at risk of significant harm. "I had some suspicions. I had no proof," he said.
When Tara's lawyer heard those words, he thought they'd won the case.
"There's an old adage in the law that suspicion is no replacement for proof beyond reasonable doubt," says Ramsland.
The court watched tape of a nine-year-old Katie's interview with police at the hospital, where she told them she'd never seen her mother do anything wrong. Then, Katie appeared as a witness and backed up what she'd said five years earlier.
The trial wrapped up on a Wednesday morning. The judge called everyone back to hear his verdict just hours later.
He found there was no direct proof that Tara had given Katie laxatives, or any concrete evidence that proved she was behind the contaminated samples. Katie was described as a "very impressive witness" with "maturity beyond her young years".
Katie had still had diarrhoea for at least 11 days after she was removed from her mum's care, and the effect of laxatives would have worn off after 48 hours, the judge said.
While prosecutors had tried to argue the microbes in the syringes and urine jars were the same as the ones in the blood culture, they'd failed to prove it, he said. There were other reasonable explanations for the situation that didn't suggest Tara had poisoned Katie.
Tara was found not guilty.
Crying, she hugged her husband, then her mum, then her lawyer. She remembers a journalist telling the lawyer he shouldn't have embraced Tara as a pandemic had just been declared. Then, she called Katie.
"It had been five years and it was finally over," she says.
"And the things that we knew, that were true all that time, were finally true for everybody else."
The words "Munchausen syndrome by proxy" weren't mentioned in the case against her, which focused on proving she'd done the specific things she was accused of. But Tara believes the profile of a Munchausen's Mum played a role.
Notes show doctors and child protection workers discussed Katie's medical history as well as Tara's behaviour in the days around the removal. Meeting notes about the case suggest that Katie's treating doctors had thought for years about Munchausen's by proxy but never had any proof. They discussed how Tara never left Katie's bedside, how she answered questions for her, and was an active blogger who was "a bit of a celebrity". The notes suggest that Tara is good at manipulating staff, has a nursing background, and was "enmeshed" with ward workers. The family was said to be "causing unbelievable stress".
Staff at the regional hospital reported that the family had at times been difficult to work with and sometimes presented late to the hospital when Katie was unwell.
"The doctors didn't like me," Tara says. "They didn't like that I research, they didn't like that I had a nursing background. They didn't like that I ask questions. They didn't like that I was a strong advocate for my daughter … I think I ticked a lot of the boxes for the profile."
Tara's lawyer, Mark Ramsland, also feels that her knowledge and advocacy about her daughter's condition may have helped fuel suspicion.
"They felt she was hypercritical of them and they were on high alert because of that. And I think that put them in a very defensive position and formed the view, erroneously, that our client was doing the wrong thing.
"I think she did alienate these doctors and once you've done that, I think systemically there's difficulties."
Alison's verdict
While Tara had been acquitted of the charges against her, Alison was still waiting to clear her name. After her mental breakdown, she was found unfit to stand trial in 2019. For three years, she hadn't been allowed to see Liam at all. It finally came to court in March 2021.
As with Tara, the case against Alison was circumstantial.
"They searched her bag, didn't find anything," says Alison's solicitor Elizabeth Tsitsos." They did a search warrant on her home, didn't find anything."
One of the most damning pieces of evidence had appeared to be what the hospital's nurses overheard Liam say about his mother poisoning him or putting something in his cannula. But the court heard he may have been delirious and on morphine at the time.
His doctor had a habit of describing the steroids he was weaning him off as "poison". And when he was interviewed by authorities at the hospital and again months later, Liam denied he'd seen his mother do anything. He said the medication had made his brain feel "empty" and go "all weird". "It's not really me saying it," he said.
Liam's father, Alison's ex-husband, also said he didn't accept Alison was capable of deliberately harming her son.
Then, there was the positive blood culture. Alison's lawyer found a doctor with twin specialties in infectious diseases and microbiology to consider how the E. coli might have ended up in Liam's blood sample. A doctor at Royal North Shore Hospital and a lecturer at Sydney University, he suggested there were other ways the faecal matter could have gotten there, including accidental contamination at the time the blood was drawn.
The court heard how Liam, who'd been diagnosed with oppositional defiant disorder, hated having his blood drawn. The night the contaminated sample was drawn, he'd been held down by four adults, making it harder to take a sterile sample. Then there were the visitors from his family: one young kid was faecally incontinent and had soiled himself in the room, and a baby had their nappy changed on his bed.
The final plank of the prosecution's case against Alison was the testimony and opinion of a key medical expert: Westmead's Professor David Isaacs, who'd first raised suspicions that Liam's IV line was deliberately contaminated.
Professor Isaacs agreed it was theoretically possible for the blood culture to have been incidentally contaminated. But he was adamant that wasn't what happened here. When the blood culture result came back from the lab he discussed it with colleagues, who agreed it was highly concerning.
"I then took it upon myself. Nobody wants to do these sorts of things … I make myself unpopular with my colleagues. But if I get it wrong, a child dies," he told the court.
"And if you get it wrong, a mother has her children taken away from her," Alison's barrister shot back.
Then, Professor Isaacs told the court a story. Once, he missed a case where the mother was harming her child. "The child died. And the mother told me afterwards what she'd been doing to that child, she told all of us," he said. "And I'm never going to miss it again if I can help it."
For Alison's lawyer, Elizabeth Tsitsos, it was "as if the penny had dropped".
If Professor Isaacs had been determined never to miss a case again, perhaps he was too vigilant in looking for the signs of induced illness, or too ready to be sure about what he was seeing.
"What if this prior experience hadn't happened? What if Isaacs was never involved in this case? Would this family still be together, would these children have grown up with their mother in their formative years? Would this woman have lost her sanity?"
A week later, the crown prosecutor stood to make his closing argument. He summarised the evidence, then came to an extraordinary conclusion.
Instead of doing what a prosecutor would usually do in this moment — driving home the case against Alison — he did the opposite. It was "quite clear," he said, that Professor Isaacs had diagnosed Alison with Munchausen's, though he didn't have the expertise to do so. He said the professor was "super vigilant" because of the tragic loss of a child years ago, and the judge might find that clouded his opinion.
The prosecutor wouldn't be arguing that there was enough evidence to prove the case against Alison.
"He basically said, 'You can't find this person guilty,'" says Alison's lawyer Elizabeth Tsitsos. "I've never seen that in my career as a defence lawyer and I expect I'll never see that again."
The next week, the judge found there was not enough evidence the organisms were introduced. Liam's symptoms could have been because he was being weaned off the steroids. He was not satisfied the blood was deliberately contaminated or, even if it was, that Alison was responsible.
She was found not guilty.
Alison's kids had always loved the piping she put on cakes. That night, Alison and her parents made a "not guilty" cake, with piping and rainbows to symbolise hope.
The system
Tara and Alison have been found not guilty, but their cases are far from behind them. Both remain furious that they ever came under suspicion from doctors like Professor Isaacs.
But Isaacs, like all health workers, is a mandatory reporter — he has a legal duty to sound the alarm whenever he has a reasonable suspicion of child abuse.
Professor Isaacs and Westmead did not respond to questions from Background Briefing. NSW Health said the safety and wellbeing of children was their number one priority and assessments are made based on all relevant information available at the time. Patient privacy prevented them from commenting further on Tara and Alison's cases.
Tara has some sympathy for the position the doctors were in — as a former nurse, she understands the responsibility of being a mandatory reporter.
"Where my upset comes in is there was no investigation," she says. "It was just an accusation, and then the removal, and then five and a half years of fighting systems to prove that I did not commit the crime that I was accused of."
The adequacy of the investigation — within the hospital, by child protection workers, and by police — is what Alison and Tara's lawyers are focused on. Doctors are experts, but no-one is infallible.
In both these cases, the treating doctors alerted the hospital's Child Protection Unit, which then brought in government child protection caseworkers and police. But these agencies were too deferential to the doctors' opinions, the lawyers say.
"This got to trial because one man pointed the finger at my client and his opinion was taken as gold by different agencies," says Elizabeth Tsitsos, Alison's lawyer.
The criminal court heard that the question of whether Liam's blood culture was deliberately contaminated was a live one from the start. Liam's respiratory doctor had thought the case shouldn't be referred to the Child Protection Unit, and then told a meeting of doctors and child protection workers that he thought Alison had responded appropriately when she'd heard about the E. coli. The Child Protection Unit never sought a report from him, though a paediatrician working with the unit said she spoke with him. A court heard he was "puzzled" that police never interviewed him either, because he was very involved in Liam's care.
Alison's lawyer, Elizabeth Tsitsos, believes other doctors and nurses deferred to Professor Isaacs due to his seniority, and this also carried sway with the state's child protection system, which doesn't have in-house specialists to review unusual and complex cases like this.
Tsitsos thinks the blood test results should have been looked at by an independent microbiologist, to see if there were any alternative explanations.
Recently, the US state of Texas has introduced a law to address similar situations, prompted by an NBC News investigation into how child protection doctors can sometimes misidentify cases of children being harmed. The law gives parents suspected of harming their children the right to a second medical opinion, even if they can't pay.
Maxine Eichner, the US law professor, says the law returns child protection paediatricians to where they should have been — no longer the last word on whether abuse has occurred, but with their allegations required to be thoroughly investigated and scrutinised by independent experts.
Mothers in Tara and Alison's position have the option to brief independent medical experts to give evidence at the Children's Court, as both women did in their criminal trials. But in a complex case, it can be difficult to find a qualified expert and they might charge tens of thousands of dollars.
The need for duelling experts could be circumvented if investigators get direct evidence, Tara's lawyer, Mark Ramsland, says. Police could have installed cameras in the hospital room to observe the interactions between Tara and Katie, he says, and this kind of surveillance is routine in other criminal cases.
NSW Police said in a statement that decisions to prosecute are made in the best interests of the child, and only when there is sufficient evidence to support criminal charges.
"NSW Health and other partner agencies do provide assistance where specialised medical and scientific knowledge can assist in the understanding of evidence or facts," the statement reads.
The NSW Department of Communities and Justice did not respond to specific questions, but sent a general description of the process they follow.
The Office of the Director of Public Prosecutions declined to comment.
The defence lawyers representing these mothers say it shouldn't have taken a criminal trial, years after the accusations were first made, to test the evidence thoroughly.
"It makes me feel very angry," says Alison's lawyer Elizabeth Tsitsos. "These are taxpayers' dollars going into a system that failed to properly investigate a case like this."
Returning home
A few months after her mother was acquitted of poisoning her, Katie moved back into the family home. Her parents had sold the house to fund Tara's legal fees but they were able to rent it from the new owner.
The walls of the Year 11 student's bedroom are packed with photos of her friends and family, a big purple tapestry ("I'm kind of into witchcraft and stuff") and paintings of animals that Tara made for her over the years. She's recently got her amphibian licence, and a glass case sits ready for a frog. She's got two guinea pigs and a puppy as well.
Katie says she packed her bags as soon as she heard she would be able to move back home. "I wanted to come home that day," she says.
When her daughter did finally return, Tara remembers Katie sitting on her bed for a long time. Then, the family sat together in the lounge room.
"There were not a lot of words," she says. "It was just being together."
Katie's health is not perfect but is much better now. She wants to let people know how easily this can happen. And she doesn't believe the doctors were acting in her best interests.
"I would try to talk to them about stuff that was going on in the hospital, but they wouldn't really listen," she says.
Being taken away from her family and placed in foster care gave her "a lot of trauma".
"I'm getting better. I still have rough days and I still find it a struggle to talk about my trauma and my emotional wellbeing," she says. But her family is helping her through it. "They're always there for me, every day since the beginning."
Tara says they've had to work hard to re-establish their relationships and work out who they are as a family.
"Our whole family was punished," says Tara. "We were all victims of that accusation. It wasn't just me. It wasn't ever just about me."
For Alison, things haven't gone as well. Her son Liam is still living with his father. She hasn't been back to the Children's Court to challenge the orders that took her children away. And she says missing out on so many years with them has made things difficult.
"My children went from being babies to … pre-teens or teenagers," she says. "I don't know how to interact with them, because I'd gone from changing their nappies to them now being taller than me, and in high school.
"The way I'd speak to them, well, you can't speak to a 14-year-old like that. They're not six any more."
These days, she just has one wish.
"Even if some of my children are still not in a position where they understand truly what's happened, I will always be here. No matter how old they are, no matter how many years it's been, my door will always be open," she says.
"I just want to be known when I die as a good mum. Not a bad mum, not anything else, just a good mum. Because that's all I ever wanted to be."
*Names have been changed to protect identity
This story comes from ABC RN's Background Briefing program. For more daring narrative journalism, listen for free on the ABC listen app, Apple Podcasts, Google Podcasts, or your favourite podcast app.
Credits
Reporter: Hannah Ryan
Illustrator: Emma Machan
Executive Producer: Tim Roxburgh
Digital producer: Annika Blau