She was just an ordinary teenager from a small village who was making her first moves into adulthood. She read Just Seventeen, liked music and was known to be a confident girl who was always polite and could make people laugh.

Vicky Hamilton was sexually active, having had a pregnancy test when she was 14 and, like many girls of her age, sometimes liked to drink. Notes found in her purse following her disappearance would suggest that she had had more than one admirer.

But the 15-year-old was maybe not as grown up as she considered herself. The weekend that she went missing was the first time she had stayed away overnight from her mother's home in Redding, outside Falkirk. It was an experience that seemed to fill her with insecurity.

She had arranged to stay at her sister's flat in Livingston and the two had a great weekend, shopping and going to a pub and disco on the Saturday night. But on the Sunday night, the 10-mile journey home seemed to overwhelm her. Her sister, Sharon Brown, 37, who now lives in Falkirk with her partner and their two children, told the murder trial that she gave Vicky instructions on how to change buses in Bathgate and get a connecting service to Falkirk "over and over again".

She had to "repeat, repeat, repeat" the directions to a worried Vicky. Despite the relatively simple journey, for Vicky it was like getting out of the jungle, her sister said.

The uncertainty of the teenager was confirmed by a number of people in Bathgate, including the bus driver who took her there, a woman who served her a bag of chips, and a man she stopped in the street. She asked them all for reassurance over where to get the connecting bus.

Keith Anderson, a retired senior officer on Operation Mahogany, the murder inquiry launched in 2006, said: "As soon as she left home that weekend, she exhibited this anxious behaviour. I think Vicky was a pretty lonely wee girl during that night. We know that she approached eight people that night, four of them male."

How she came into the company of Peter Tobin only he knows, but detectives believe she could have approached him too for directions to the bus stop.

There were no sightings of the two of them together, and no proof that Tobin drove her in his car. It is not known exactly what happened when the two arrived at his house in the town's Robertson Avenue.

All that remained of the encounter was her bruised body, cut in two and buried in Kent, with traces of sedative found in her liver, and a sliver of Vicky's skin on a hunting style-knife in the loft in Bathgate.

Vicky's mother, Janette, died in 1993, never knowing what happened to her daughter. The remaining members of her family were left shell-shocked by a 17-year wait dotted with raised hopes but crushed by numerous hoaxes, including "information" offered by more than 20 mediums.

The family had already been split by the break-up of Janette and Michael Hamilton in 1989, after which Vicky and her younger twin brother and sister, Lindsay and Lee, stayed with their mother and Sharon moved into a flat with a friend.

As the strain of Vicky's disappearance took hold, the fracture within the family grew deeper and was painfully clear at Vicky's funeral in Redding on November 30, last year.

Rows broke out over where her body should be laid to rest. Sharon insisted it was their mother's last wish that Vicky should be placed with her in Polmont. Mr Hamilton, however, wanted his daughter to be buried in his plot outside the village where Vicky lived.

The split was on obvious show during the service. Mr Hamilton sat comforted by his second wife, Caroline, while Sharon was across the aisle with twins Lindsay and Lee, now 24 but just six when Vicky disappeared.

At the graveside, Sharon and her father each took a cord of Vicky's coffin. It was a shared act of love for their lo st sister and daughter, but one that ultimately failed to bond them.