As a journalist I've covered thousands of stories.
Many of them are forgotten about by the end of the week - sometimes I come across a piece I've written and can't even remember doing it. But the murder of 13-year-old Billie-Jo Jenkins was different. Every reporter tends to have a case they return to over and over again; mine is Billie-Jo's.
Her young life was ended on 15 February 1997 in a brutal and shocking act of violence: she was battered over the head at least five times with a metal bar - an 18-inch iron tent peg.
The fatal attack took place at her home at Hastings, in East Sussex. Billie-Jo had been painting at the back of the house where she'd lived for over four years with her foster parents and their four young daughters. By coincidence, they were also called Jenkins. Nine days after she died, her foster father, Sion Jenkins, a secondary school deputy headteacher, was arrested on suspicion of murder. Jenkins was later given a life sentence, spending six years in prison before his conviction was quashed. By then, the case had become a 'cause celebre'.
At the time of the killing, I was working for the BBC as a junior reporter. When Jenkins was charged I was dispatched to Hastings Magistrates Court to cover the hearing. The following year, I squeezed into the press box at Lewes Crown Court just before the jurors returned to deliver their unanimous verdict of guilty at the conclusion of a dramatic and emotionally-charged trial. Since then, I've spoken to many of those involved in the case and reported on the two Court of Appeal hearings and two re-trials at the Old Bailey - both of which ended in a hung jury and, ultimately, Jenkins' acquittal in February 2006.
Next month will mark the 25th anniversary of Billie-Jo's murder. Inevitably there will be some media interest - a television documentary is due to be shown - and no doubt there will be renewed speculation about possible suspects. It will be a difficult time for those who loved Billie-Jo; although the passing years may have dulled their sense of loss, for some the memories of that dreadful Saturday afternoon and its aftermath are still vivid. The pain sometimes resurfaces; and the fact that the killer has not been brought to justice and remains at large heightens their sense of unease and anguish.
Officially, the case remains open.
Sussex Police tells me that it forms part of its review team's "schedule of unresolved investigations". In a statement, the force says: "Each unsolved homicide is assessed two-yearly, to examine any new information that may have become available, or to consider any advances in investigative techniques, that would make re-opening the investigation viable.
"Currently no new information has been provided in this case and it is not being re-investigated," it says. "However, as part of the regular assessment process, we are currently carrying out a forensic review of material held on the case in order to establish whether or not scientific advances can provide new evidence or lines of enquiry."
The forensic review is a welcome step; I understand it is detailed and has been going on for some months. One aspect that the police team is believed to have considered concerns evidence from Jeremy Skepper, who worked at the multi-imaging centre of the department of human anatomy at the University of Cambridge. Dr Skepper, who's now retired, had used an electron microscope to examine the scientific centrepiece of the Prosecution case - bloodspots.
After the murder, about 150 tiny spots of Billie-Jo's blood were found on Sion Jenkins' trousers and fleece jacket. The Prosecution argued that their size and distribution were consistent with 'impact spatter', caused, they alleged, when Jenkins repeatedly struck Billie-Jo on the head with the tent peg. The Defence maintained that a fine spray of blood was breathed out by Billie-Jo onto Jenkins when he tended to her as she lay dying.
At the second trial, Dr Skepper asserted that some of the bloodspots contained white particles which he said could be damaged skin tissue from Billie-Jo's scalp. Defence experts contested the claim. On the eve of the third trial, the Prosecution tried to introduce new evidence from Dr Skepper. Having conducted fresh examinations, he reported that microscopic fragments of bone, paint and metal could also be present in the bloodspots. The Prosecution regarded this as important because it appeared to bolster the tent peg theory. The Defence were sceptical and said they would need to commission their own scientists to study the results, which they estimated would take about three months. The judge, Mr Justice David Clarke, said the material had been submitted too late; he refused to delay proceedings - and the new bloodspot evidence was never heard by the jury.
It is hard to gauge what effect Dr Skepper's new findings would have had on the outcome of the trial had they been presented. You can be sure that the Defence would have produced at least one expert to counter his evidence. Disputes about the provenance of material in the bloodspots were already raging; the scientific arguments in court were so complex, with a range of opinions from a variety of specialists, that adding an extra element would probably have served only to create more confusion.
It is understandable, however, that there may be renewed interest in Dr Skepper's results - after all, the 'bone, paint and metal' findings were never tested in court. Advances in science have provided the key to unlock a number of unsolved crimes, and I sincerely hope it happens in this case. Sadly, though, my sense is that it is unlikely because a great deal of scientific work, by Dr Skepper and others, had already taken place and was known about at the time. Some items were tested and re-tested and may well have degraded. Of course, it remains a possibility, just as there is always the chance that a witness will come forward with previously undisclosed and crucial information - though given that the events occurred a-quarter-of-a-century ago their testimony would rightly be treated with caution.
In fact, for some time, my view of the case has been that the only realistic prospect of delivering justice would be if the person responsible for Billie-Jo's murder decided to confess. What they did must still weigh heavily on their conscience. Perhaps, just perhaps, publicity around the anniversary will encourage them to relieve themselves of the burden that they have been carrying for 25 years.
Sussex Police say anyone who has new information that could lead to new lines of inquiry in the case should contact them by calling 101, quoting Operation Cathedral.