The family of tragic Sunderland schoolgirl Nikki Allan have been fresh hope with the news that prosecutors may be able to charge a new suspect with her murder.
This is a timeline of the events which have unfolded since the seven-year vanished near her home in Wear Gareth, in the city's East End, in October 1992.
October 7, 1992
Nikki Allan vanishes on the short walk home from her grandparents’ flat in Wear Garth. Nikki sets out for home to head down a stairwell and across a short corridor, but when mum Sharon follows down the stairs shortly after, she is nowhere to be seen. More than 100 people join in the search for her.
October 8, 1992
Nikki’s battered body is discovered the next day in a pool of blood in the derelict Quayside Exchange building in High Street East, just yards from the Garths. Nikki’s body is identifed by her grandfather Dickie Prest.
October 9, 1992
Police tell the media that a house-brick was the likely weapon used to batter Nikki to death. A ‘blood-covered’ man is arrested.
October 11, 1992
The suspect is released without charge.
October 12, 1992
An artist’s impression of a man seen in the area with a girl at the time of Nikki’s disappearance is issued by police.
October 13, 1992
Police issue a composite picture of Nikki in the clothes she was wearing at the time of her disappearance.
October 14, 1992
A reconstruction is staged of Nikki’s last known movements, starting outside The Boar’s Head pub.
October 18, 1992
Neighbour George Heron is charged with murder
October 19, 1992
A large police presence assembles at Sunderland Magistrates Court as Heron appears in the dock for the first time.
November 21, 1993
A murder case against Heron collapses after a judge at Leeds Crown Court accuses police of heavy-handed tactics and refuses to admit a taped confession as evidence. Heron is found not guilty by a jury at Leeds Crown Court after a six-week trial and later tells the Echo he feels he will not be able to return to the North East. The trial had lasted six weeks. Heron had spent 13 months in custody.
Sharon Henderson brings a civil case against Mr Heron, charging him with “battery on the child, resulting in her death.” A court finds in her favour and orders Heron to pay over £7,000, but he cannot be traced and the money is never paid.
A Crimewatch reconstruction puts the case firmly back in the public eye. The programme produces a number of new leads - but no arrests.
Northumbria Police arrest Sunderland serial killer Steven Grieveson, on suspicion of Nikki’s murder. He is questioned and bailed and Sharon Henderson writes to him, asking him to cooperate with the inquiry, but detectives later say his bail had been cancelled and he will face no further action.
In the run-up to what would have been Nikki’s 30th birthday, Sharon describes the family’s feelings at the lack of progress on the case: “We’re just devastated after all this time, we’ve got nothing.”
Sharon Henderson calls for a full reinvestigation of the crime. She launches an on-line petition urging Northumbria Police to carry out a top-to-bottom review of the case, which attracts more than 500 signatures in less than 24 hours.
Sharon again writes to Steven Grieveson, urging him to share anything he may know about Nikki’s death. “I know he received my last letter but he didn’t answer,” she says. “But you never know, he might decide to respond this time.”
Northumbria Police dedicates a new forensics team to finding Nikki’s killer ahead of the 25th anniversary of her death. Sharon meets with Northumbria Police chief Constable Steve Ashman and other senior officers at the force’s headquarters to discuss the latest developments in the case. She says: “They will be on it all the time, not moved about, and will be dedicated to Nikki’s case. “They are hoping to make it their number one priority - not just the DNA, the whole thing from the beginning.”
Police said they had succeeded in recovering new DNA from an unknown male. They appealed for anyone who came into contact with Nikki before she went missing to come forward and give a mouth swab sample so they can be ruled out of the inquiry.
A man was arrested on suspicion of murdering Nikki. Sharon Henderson told the Echo: ""They came to see me and said 'We have arrested somebody for Nikki's murder'. My legs went. I can't describe it, I was like a little bairn. I was saying 'Is this real? Is this real?'" After being questioned, the suspect was released.
Related: New arrest in hunt for killer of Sunderland schoolgirl Nikki Allan
Sharon Henderson appears in court charged with an offence under the Communications Act over comments on her Facebook page. She is found not guilty after she agreed to a restraining order. During the case her solicitor Jason Smith says: "All Miss Henderson is interested in is that gentleman who was arrested, who we understand the CPS may well have authority to charge him with that murder."