The sister of missing Pyramid Hill woman Krystal Fraser has told a coronial inquest she thinks the unidentified father of her sister's unborn child knows what happened to her sister.
Ms Fraser, who had an intellectual disability, was 23 and just days away from giving birth when she disappeared on June 20, 2009.
She had already named her unborn son Ryan, but had told her parents and sister she was unsure who the father was.
Her sister Chantel Fraser told the inquest in the Coroner's Court in Melbourne this morning that while researching the case for a book with a former policeman, she learned there had been an argument between two men about killing Ms Fraser.
She said a witness had overheard one of the men saying to the other that they should not go through with killing Ms Fraser because of the unborn baby.
Chantel Fraser said, in response to questions by counsel assisting the Coroner Fiona Batten, that Peter "PJ" Jenkinson was "always in the picture".
He is the man the inquest has heard is Victoria Police's primary suspect and a possible father of the baby.
"He's the only bloke she would return to Pyramid Hill for," Chantel Fraser told the inquest.
She told the court Mr Jenkinson had stopped using a mobile phone or landline to call Ms Fraser and used payphones instead.
Family concerned about Krystal's ability to be a mother
The court heard Ms Fraser was highly vulnerable due to her intellectual disability and it was "highly unlikely" she could care for a child independently.
The court also heard that while in some ways she was very "switched on" – particularly when it came to technology – in others, she was naive.
The court heard the family feared Ms Fraser was being used for sex and had become associated with drug dealers in Gunbower, transporting cannabis between Bendigo and Pyramid Hill by train.
"She kept saying, 'If you hear any rumours about me and drugs, it's not true,'" her mother Karen Fraser told the court.
"She said, 'If I do get caught, I'm a nuffer, they'll just slap me on the wrist.'"
The court heard the "undesirable" men knew Ms Fraser was paid by the government on a Monday, Wednesday and Friday and would get her to buy them beers or cigarettes.
Mrs Fraser said her daughter did not have a formal diagnosis for her intellectual disability because when the time came for the assessment she had turned 18 and chose not to do it.
'I think somebody killed my daughter'
On the morning of her disappearance, Ms Fraser discharged herself from Bendigo Hospital's Medi-Hotel, saying she was going to a party.
A witness told the inquest she was on edge the night she returned to Pyramid Hill as she waited for someone to pick her up from the pub.
She was last seen leaving an address at Albert Street in Pyramid Hill that night.
At 11.59pm, Ms Fraser received a 40-second call on her mobile from a public phone booth outside the Leitchville Post Office on Findlay Avenue.
Police believe they know who made the call, and that this person was either involved or has a good knowledge of what happened to Ms Fraser.
Her phone later showed activity at a Leitchville Tower – about 27 kilometres from Pyramid Hill – at 2.49am on June 21.
The court heard Ms Fraser could not have walked the distance to Leitchville and she couldn't drive.
"I think somebody killed my daughter," Mr Fraser told Ms Batten.
Handwriting on suicide note questioned
Ms Fraser's parents told the court they did not believe their daughter died by suicide after they were directed by Ms Batten to read a suicide note purportedly written by Ms Fraser.
Mr Fraser said the note couldn't possibly be his daughter's because the handwriting didn't match.
"I don't believe she wrote that. The words are wrong," Mr Fraser said.
Ms Batten asked whether the contents of the letter could have been dictated to Ms Fraser.
"There are too many capital letters in the letter. She wouldn't know what an apostrophe was. She knew any word, but couldn't tell you what it means," Mr Fraser said.
Potential fathers named in inquest
Ms Fraser had mentioned she had taken steps to identify the father of her unborn son to receive child support.
She told her parents three men could have been the potential father; Mr Jenkinson, Tony Gatt and Gareth David.
In June, detectives issued a fresh plea for public information to help solve the mysterious disappearance. A $1-million reward remains on offer for information that would solve the case.
Ms Fraser told her parents in early 2009 that Mr David could be the father.
On Tuesday, Mr David sought to correct the record, saying he did not have sex with Ms Fraser down an alleyway behind a Bendigo pub in about August or September 2008, despite accepting he could be the father in an earlier police interview.
"I really don't think I had sex with Krystal," he told the inquest.
"I asked police to change that but it looks like they didn't."
Twenty-three witnesses are set to be called as part of the inquest.
