Paul Aiton leaves jail after serving 19 years behind bars for the murder of Daniel Valerio. Photo / Supplied
While every murder case attracts significant public interest, stories behind the killings of innocent, defenceless children shock like no other.
These are some of Australia's worst child killers and the stories behind the vile crimes that robbed kids of their lives.
KATHLEEN FOLBIGG
Convicted and sentenced in 2003 for the manslaughter of her first child and the murder of her next three children, Kathleen Folbigg is one of Australia's notorious female child killers.
Despite multiple failed attempts to clear her name, Folbigg continues to deny killing her children and her supporters argue she has been the victim of a miscarriage of justice.
Folbigg's first child, a boy named Caleb was born in February 1989. He was found dead in his bed 19 days later.
Her second son Patrick died at seven months of age in October 1990.
Folbigg's first daughter and third child Sarah was born in October 1992. She died aged 10 months, in August the following year.
Laura was Folbigg's second daughter to die. She was aged 18 months at the time of her death in March 1999.
In sentencing Folbigg to at least 30 years behind bars, which was later reduced to 25 years on appeal, NSW Supreme Court Justice Graham Barr said the child killer carried out the murders by suffocating her babies.
The court heard Caleb died from an act of smothering "carried out in the heat of uncontrollable anger by a young and inexperienced woman of prior good character".
Patrick died after Justice Barr said Folbigg "decided to rid herself of the child whose presence she could not longer tolerate".
"The stresses on the offender of looking after a young child were greater than those which would operate on an ordinary person because she was psychologically damaged and barely coping," Justice Barr said of Folbigg, who was aged just 18 months when her father murdered her mother.
"The attacks were not premeditated but took place when she was pushed beyond her capacity to manage. Her behaviour after each attack contained elements of falsity and truth … she falsely pretended the unexpected discovery of an accident and falsely maintained her innocence.
"However her attempts to get help, including what I think was a genuine attempt to perform cardiopulmonary resuscitation on Laura, were genuine and made out of an immediate regret of what she had done. Her anger cooled as fast as it had arisen."
MARTIN BRYANT
The man behind Australia's worst mass shooting ended the lives of 35 innocent civilians during the horrific Port Arthur massacre in 1996.
Alannah, 6, and Madeline Mikac, 3, were the youngest of Martin Bryant's victims.
The young sisters died alongside their mother Nanette, while attempting to escape the carnage.
More than two decades later, in a heartbreaking interview for television series Anh Do's Brush With Fame, Walter Mikac broke down as he recalled the final moments of his wife and daughters' lives.
"The car with the gunman came up the hill," Mr Mikac said.
"Nanette was running with the kids. She was carrying Maddie. There were other people who overheard her saying, 'We'll be safe if we just keep running and we're away from here'.
"The car stopped and the gunman got out. She pleaded with the gunman for the childrens' lives. She said 'Please don't kill my children'.
"He shot her and then he shot the children. Alannah was hiding behind a tree and he actually went up to her and shot her there."
Tasmania's Supreme Court heard Bryant showed no remorse for his actions.
For the murders of 35 people in the massacre, Bryant was handed 35 life sentences and ordered never to be released on parole.
RACHEL PFITZNER
After killing her two-year-old son, Rachel Pfitzner wrapped his body in plastic, stuffed it in a suitcase and wheeled it in a pram to a pond in Ambarvale in Sydney's southwest.
When she threw the suitcase containing Dean Shillingsworth into the pond, Pfitzner watched it sink before she turned her back and walked away.
A group of schoolchildren were the first people to discover the suitcase floating in the pond six days after Pfitzner disposed of him in October 2007.
When questioned initially by police, the NSW Supreme Court heard Pfitzner lied about Dean's whereabouts and claimed she abandoned him at the Campbelltown Department of Community Services office.
Her story later changed and she claimed his death was an accident, telling police "I shook him … He stopped breathing and I tried resuscitation … I've got to live with this for the rest of my life but the media are portraying it as if it is real evil".
In a secretly recorded conversation Pfitzner had with her mother after her arrest, she said "he never got suffocated … I choked him".
During an interview with a psychiatrist Pfitzner said "I told him to go out and play … he wouldn't listen … then I lost it … I grabbed him by the shirt and jumper which had a hood and shook him … the next thing I remember he was frothing at the mouth".
As he sentenced Pfitzner and outlined her shocking treatment of Dean, Justice Robert Hulme said the cause of death was asphyxiation.
"She became resentful of his presence and was critical of his behaviour," Justice Hulme said of Pfitzner.
"She sometimes banished him from the house, forcing him to stay outside in the cold. Neighbours described Dean being locked out of the house and hitting the doors while crying and trying to get back inside. He was repeatedly heard to cry out, 'Mummy mummy I am sorry
"Dean was often hungry and would forage for food but she punished him for doing so. Dean would seek the offender's affection but this would cause her to become angry as she thought he was being overly clingy."
Pfitzner was sentenced to at least 19 years behind bars for murdering Dean.
ROBERT LOWE
Paedophile Sunday school teacher Robert Lowe abducted and raped 6-year-old Sheree Beasley before choking her to death and stuffing her into a drain.
Before she was murdered, Sheree rode her bike to a milk bar at Rosebud on Victoria's Mornington Peninsula in June 1991.
On the way home she screamed as Lowe pulled her off the bike, put her in his car and drove her to a remote area where she was sexually assaulted and killed.
Afterwards Lowe disposed of Sheree's body he dumped her pink bike helmet in a bin near his home.
Her body was found almost four months later.
Lowe became a prime suspect after he lied to police about his whereabouts on the day Sheree died.
Child abuse material and newspaper cuttings about Sheree were found at his home.
Police later discovered Lowe had a history of exposing himself to children.
Without hard evidence, police conducted surveillance of Lowe for two years.
When he was arrested for shoplifting, a murder confession he penned was found in his pocket.
Lowe died in jail in November 2021 while serving a life sentence for Sheree's murder.
JOHN SHARPE
Former banker turned conveyancer John Sharpe used a speargun to kill his 20-month-old daughter Gracie in March 2004 at their home in the Melbourne suburb of Mornington.
She was shot four times four days after her pregnant mother Anna Kemp was also killed at the hands of Sharpe.
The Victorian Supreme Court was told Sharpe used a chainsaw to dismember his wife's body and he disposed of his family's remains at the Mornington rubbish tip.
In the immediate aftermath of the murders Sharpe tried to claim Anna left him for another man and took Gracie with her.
Police later discovered Sharpe had used Anna's ATM card at a bank and emailed her mother, pretending to be Anna.
Eventually Sharpe confessed and when asked why he killed Gracie he said he did not know.
"When you're sort of insane, your mind's all over the place," he said.
Sharpe is currently serving two life sentences for the murders. He will be eligible for parole after 33 years behind bars.
KRISTI ABRAHAMS
Kristi Abrahams reported her 6-year-old daughter Kiesha Weippeart missing in August 2010.
She repeatedly denied any involvement in Kiesha's disappearance, however, less than a year later Abrahams was overheard making admissions regarding her daughter's death in secret police recordings.
The NSW Supreme Court heard Abrahams claimed Kiesha hit her head on a bed about two weeks before she was reported missing from her home at Mt Druitt in Western Sydney.
When Abrahams woke up the next morning, she said Kiesha was not breathing.
Several days after her daughter's death, Abrahams and her partner Robert Smith grabbed a suitcase and travelled to a burial site at Shalvey to dispose of the body.
"Mr Smith dug a hole … tipped the deceased's body out of the suitcase into the hole, poured petrol on the body and burnt it," Justice Ian Harrison said as he sentenced Abrahams who pleaded guilty to murder.
While Abrahams' version of events about what caused Kiesha's death were rejected by Justice Harrison, he said there was a "total absence of any reasonable explanation for what happened".
"No motive for the offence has emerged.
"Precisely what happened when the deceased was killed would seem to be known only to the offender and Mr Smith."
Abrahams was convicted of Kiesha's murder and sentenced to at least 16 years behind bars.
After pleading guilty to manslaughter and being an accessory after the fact, Smith was sentenced to at least 12 years behind bars.
GREGORY DAVIES
While walking home from the shops, 6-year-old Melbourne schoolgirl Kylie Maybury was snatched by Gregory Davies and pulled into his station wagon.
After drugging Kylie with sleeping medication, Davies raped and suffocated her in his car on Melbourne Cup Day in 1984.
The next day Kylie's body was found in a gutter 650m from the house Davies lived at with his mother.
He kept his crime a secret for more than 30 years, until 2016 when his DNA was matched to semen found on Kylie's clothing and body.
In 2017 Justice Lex Lasry to life behind bars for the rape and murder of Kylie.
"They were terrible offences … this child did nothing except walk to a shop and at the age of six years she lost her life in the process," Justice Lasry told Davies.
"You have killed a defenceless child after raping her.
"You lied to police for a time, you kept what you had done to yourself for 33 years. I wonder how you were able to do that."
PAUL AITON
For several months before his final fatal act of violence, Paul Aiton bashed and tortured two-year-old Melbourne boy Daniel Valerio.
In September 1990 as Daniel lay sick in bed, Aiton punched his stepson several times in the stomach and killed him by crushing the toddler's internal organs.
The doctor who performed an autopsy on Daniel's body compared the damage inflicted to that of a road crash victim.
In the months leading up to his death, 21 professionals had seen Daniel and none intervened.
His death sparked landmark reforms which required health, education. and law enforcement workers to report any suspicion of child abuse to higher authorities.
After Aiton served 19 years behind bars for Daniel's murder he was released on parole in 2011.
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