BILLIE-Jo Jenkins was 13 years old when she was murdered in 1997.
The case has since been described as one of the UK's most notorious unsolved murders. Here's what we know about her death.
Who killed Billie-Jo Jenkins?
The murder of 13-year-old Billie-Jo Jenkins has not been solved, 25 years after the tragic incident.
A documentary about the murder, called Who Killed Billie-Jo? aired on February 10, 2022.
Retired detective Jeremy Paine who worked on the original probe into her death appears in the Channel 5 show.
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He told the Mirror in February 2022: “This was a tragic and brutal act of violence.
"Billie-Jo had her whole life in front of her.”
Paine said he still hopes that developments in forensic technologies will one day solve the mystery.
Her case is one of the UK's most high-profile unsolved murders.
What happened to her?
On February 15, 1997, Billie-Jo was painting the patio doors at the back of her foster home in Hastings, East Sussex, when she was struck at least five times on the head.
She was found in the back garden of the family home, bludgeoned to death with an iron tent peg.
At the time, she was reportedly alone, with the rest of her family out of the property.
The schoolgirl had been living with her foster family for five years before she was brutally killed.
Who were the suspects in Billie-Jo's murder?
Fingers were pointed towards her foster father Siôn Jenkins who faced a total of six years in prison before being acquitted of the crime on February 9, 2022.
When the foster dad returned to the house following a trip to a DIY store, with his two oldest daughters, he found Billie-Jo dying, in a pool of her blood.
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Police initially asked Siôn to make a public appeal for any information, but shortly after he became the main suspect.
He was arrested nine days later on suspicion of murder, and was charged with murder on March 14, 1997.
Siôn - father to Annie, 12 at the time of the murder, Lottie, 10, Esther, nine, and Maya, seven - has always maintained his innocence and claims a prowler could have been responsible for the murder.
During the investigation, police discovered 148 tiny spots of Billie-Jo's blood on Siôn's trousers and fleece jacket.
The prosecution argued that their size and distribution were consistent with "impact spatter", sprayed during the frenzied attack on Billie-Jo.
But the defence argued that a fine spray of blood was breathed out by Billie-Jo on her foster dad when he went to her aid as she lay dying.
Siôn spent six years in jail following his sentence.
In the following two retrials, the jury was unable to reach a verdict, and Siôn was formally acquitted in 2006.