Margaret Glachan believes locals beat 14-year-old Caroline, of Ladyton, Bonhill and left her to die in the River Leven on August 24, 1996.

Speaking days before the anniversary of her daughter’s unsolved murder, Margaret said it is now time that those responsible were brought to justice.

She said: “It’s time. It’s time they came forward to give up what they know. To take a look at themselves, and their conscience, if they’ve got any. It’s time it was finished and it’s time I had peace.” Caroline was killed while taking a shortcut from Bonhill to Renton to meet her boyfriend, on her mother’s birthday.

Margaret, now 58, said she will never be able to forget what happened to her daughter but bringing those responsible to court would give her some closure.

She said: “It’s horrendous. It’s just constant, you just still think about it constantly. It won’t be until we get them for the murder that you’ve got the closure.

“The two questions which are constantly going round my head are why and who. I need to know and have them look at me and tell why they thought it was necessary.

“That’s my two burning questions.” She added: “I would say they are local. They are definitely local. That’s the thing, you are walking about down the Vale going out to the shops and its just hanging over you all the time.

“I want people to give me a bit of peace. It’s as if I’m doing the life sentence. It’s just constantly there all the time – how they even live with themselves all this time, it’s beyond me.

“It’s time to give up what you know.

“The case is still open and they are still investigating. The police need the public as well so if there is someone that does know something it’s time they came forward.” Caroline’s best friend and one of the last people to see her alive was Joanne Menzies.

They spent the evening together before Caroline decided to go and see her boyfriend at around 11.30pm.

Around an hour later a scream was heard from the banks of the river.

A man in a hooded top was seen standing around 30 yards from Caroline as she walked along Dillichip Loan at about 12.15am on the day of her murder.

Someone fitting his description was spotted about half an hour later running down the main street of Alexandria with another man.

Both have yet to be traced.

Joanne, now 34 and studying criminology and psychological studies, said she has never been able to get over what happened to her best friend.

She said: “I was 15 at the time. The enormity of what happened never hit me. I put it in a box at the back of my mind.

“I still kind of live in fear because I’ve got three kids. I’m scared in case they do it to them. I would love to see them taken to justice. They are on Facebook and they have kids of their own. Margaret is just surviving to find out who it is.” She added: “I left Caroline at 11.30pm and she was dead at 12.45am. I still get nightmares. The guilt I carry is terrible. I feel guilty that I never went with her. I’ll never have another best friend. It’s a child killing we are dealing with. She was always a bright lassie, always cheery and happy. She was a 14-year-old girl.” After Caroline’s murder, Joanne suffered another heartbreak when her first love and the father of her eldest daughter, Paul Murray was murdered in 2011.

His killer Terence Maginn was caught and is now serving 20 years and Joanne said she wants Margaret to have the same kind of closure for Caroline.

She said: “I was a double blow, it was Caroline and then my first ever love. We got together when I was 14. At least they got that guy. As horrible as the murder trial was – it still hurts – it’s still closure and that guy got 20 years. I always know he’s behind bars but all these years waiting and we’re trying to get these other people. How they got away with I don’t know.

“I just wish she was back. I wish that Margaret could get that closure.

“It still hurts as much as it did back then. It’s still painful. The nightmares are worse. It’s as if she’s in my dreams speaking to me telling me to help her.” “Maybe if they catch someone I’ll be able to move on a bit better.

“I just hope something comes out of this. They still stay around here, some of the people that done it. I hope they have some conscience and hand themselves in now.”