A woman has said the youth justice system has failed after she listened to her teenage son's killers being sentenced for a second time in less than two years.
Angus Beaumont, 15, died just over an hour after he suffered a stab wound to the chest at 8.10pm on March 13, 2020 in a car park in Redcliffe, north of Brisbane.
Two teenagers were given detention orders in the Brisbane Supreme Court on Friday over Angus's death during a knife fight beside a suburban road.
Angus' mother Michelle Liddle attended the hearing, which marked the end of an ordeal that included both teens being found guilty of murder by a jury in June 2022.
Ms Liddle, crying at times, said the judge was restricted in the length of sentences they could hand down by the laws in Queensland.
"They said the (offenders) were traumatised; our family is traumatised ... I can't believe this is how the system runs," she said.
The teens successfully appealed their convictions in July 2023 and were granted a retrial.
A judge-only trial in December 2023 found one teen, aged 14 at the time and given the pseudonym TAZ by the court, guilty of murder.
Another 14-year-old known as SED was found guilty of manslaughter.
TAZ was on bail for armed robbery and SED was on probation when Angus was killed.
SED bought a $25 "stick" of cannabis from Angus and his 16-year-old friend at a skate park.
TAZ later emerged from a nearby toilet block with a knife and demanded their money back, claiming the drugs were underweight.
TAZ and SED chased Angus and his friend through the park until they reached Anzac Avenue.
Angus was handed a knife and knuckle duster from his friend moments before a fight with TAZ and SED, which lasted just seconds.
Justice Sean Cooper found SED aided TAZ in the fight but did not expect him to kill or inflict grievous bodily harm.
Prosecutor Chris Cook told the court on Friday that TAZ had committed serious offences while on bail.
"He is a New Zealand citizen and is liable for deportation," Mr Cook said.
Mr Cook said Angus' parents did not want to go through the trauma of writing another victim impact statement.
"Nothing can bring Angus back … their sentence is one for life," Mr Cook said.
TAZ's barrister Patrick McCafferty said his client was genuinely remorseful and had stated "if I could take it back I would".
"His childhood was horrendous, he was exposed to what no child should be exposed to: drugs and domestic violence," Mr McCafferty said.
Mr Cook said SED had also committed offences while on bail and had been involved in at least 27 violent incidents while in detention.
SED's barrister Jacob Robson said prosecutors had turned down his offer to plead guilty to manslaughter.
Justice Cooper said TAZ and SED were the aggressors in the knife fight as Angus just told them to go away.
"A mistaken belief that you were ripped off … had tragic consequences and a devastating impact on Angus' family," the judge said.
TAZ was convicted and sentenced to a nine-year detention order with release after serving 60 per cent of the term.
SED was convicted and sentenced to a detention order for five years and six months with release after 50 per cent of the term.
Ms Liddle said Angus had made a silly mistake and tried to protect his friends. Now his siblings had lost four years of their childhood.
"(Angus) was somebody who had a future, he wanted to have a small business, he wanted to do things with his life, he never wanted to go out and kill people," Ms Liddle said.
