The light from the circle of candles flickered and danced.

One for each teenager at the holiday camp, thought 16-year-old Jenna, looking around at the friends she had made in the past week. It was the final night and, as one of the leaders said a prayer for them all, Jenna felt the emotion building, inside herself and inside the room.

"Then this boy just burst out crying," she recalls, incredulity at the memory still obvious in her voice. "I had never seen a boy cry before and I thought, oh my -"

The boy was a trigger. Tears ran down Jenna's cheeks and she saw many of the others were crying too. She didn't know why. It didn't really matter why. The other kids were from "ordinary" backgrounds but perhaps everyone had secrets. Jenna had arrived at camp with her own. Her mum, Hazel, was in prison and, at 16, Jenna had been left alone, caring for herself and her nine-year-old brother, Charlie. She and Charlie had been offered a week away at Lendrick Muir, Kinross, where no-one would know their background. It was a pilot project organised by three charities: Circle, which supports disadvantaged children, Prison Fellowship Scotland and Scripture Union (SU) Scotland, which already specialised in activity holidays for children and teenagers.

Jenna, who impressed leaders so much that she has been asked back to train as a holiday camp leader next year, could become a sister again instead of a surrogate mum. However, she didn't simply benefit from the challenges of kayaking and gorge-walking. She benefited from realising she wasn't so different after all. Seeing a boy cry for a reason she didn't understand made her realise that everyone in the world has their own back story, their own inner challenges: "I was with people who didn't know me and didn't judge me. I realised that it doesn't matter what people think of you. It genuinely doesn't. I thought: that's the attitude. Just get on with it."

Jenna's back story: Running free, up the street, with friends, towards her mother's car, parked outside her house. Jenna is 15 and going ice-skating. The world is simple. When the police appeared, it felt as if they simply materialised from every corner, around every building. At first, she thought there was a fight until the police surrounded her house. She looked at her mother, Hazel, in bewilderment. It was only later, when Jenna was taken in and questioned by police, when the media ran stories about her mother possessing cocaine, that the anger came. "I was raging," she says, while Hazel looks on quietly beside her.

There is a silent bond in this family. Jenna and Hazel tease, scold and glance at one another with wry amusement. Charlie plays on a computer. He is very deep, says his mum. He is also artistic and spent three hours moulding and painting a ceramic skateboarder for her, with "No Fear" written across the base, when she was in prison. Hazel kept it in her cell. "I was really impressed watching him paint that," says Janet Stewart, a manager with Circle. "He was so clever and astute about using things that would make his mum think of him."

Charlie appears not to be listening to adult conversation, even when he is. He has soft eyes. They do his talking for him. He only cried once, says Hazel: when she phoned to tell him she was being released after 18 months.

Hazel has learned how easy it is to get in serious trouble without trying. She kept a package in her house for a family friend she had known for more than 20 years, she explains. Yes, if she's honest, she guessed what it contained but she didn't ask. The police followed the man to her house but he escaped and, the next thing, her house was raided. Her friend's package was found to contain a kilogram of cocaine. Ex-friend now. She didn't expect him to give himself up, but she did expect him to help her two children. He didn't, even though Hazel was looking at a substantial sentence. "The judge accepted I was just a safe house but it doesn't make any difference if you're dealing or not. If you're caught with drugs, the rest doesn't matter."

Jenna lay on her bed staring into space the day her mum appeared in court. Waiting. Then the phone rang. "It was my gran and my heart stopped. I walked into Charlie's room and he just looked up and asked, 'Is mum away?'. I said 'yeah'. I took him to get a McDonald's to try to take his mind off it."

Hazel looks at Jenna, tears rolling down her cheeks. "I thought the tears were all away," Hazel says. "It was the worst day of the lot."

In the run-up to the trial, Hazel's mum died. Jenna and Charlie had grown up without their dad, but his mother, their other gran, offered to help. However, she lived in an area Jenna wanted to stay away from so, instead of moving there, Hazel signed over her house to Jenna when she turned 16 so she and Charlie could stay on. It would be tough, but Jenna thought she could manage, even though she was still at school. Before going to court, Hazel contacted every organisation possible to set up assistance for her children. Given Charlie's age, she anticipated a lot of help but, once in Cornton Vale prison, everything fell apart.

"I had been promised all this support but it just didn't happen," she says. "I can't tell you how I got through the first six weeks. It was just constant stress. It got to the stage where I felt like going totally, totally crazy."

Jenna was going crazy too. She was frightened and confused: "I didn't even know how to use the washing machine." She and Charlie simply co-existed, drifting by one another in a house that no longer had any centre. "Charlie was angry as well and he took it out on me a bit," she explains, but occasionally, he would ask for a cuddle which unnerved her. "I would think, 'oh son -'"

She didn't really know how to respond but she tried to make Charlie her priority. "I did my best. I got him off to school, but everything was a blur."

Charlie stayed over with his gran more and more often. "I was just getting through the week and then at the weekend it was drinking," admits Jenna.

In prison, Hazel spotted a poster for Circle that changed everything. After seeking help, a Circle worker was appointed who contacted Jenna every single day. Crucially for Hazel, she not only kept her informed about what was happening at home – good or bad – she brought Jenna and Charlie to the prison every week. "It was a bit emotional the first time," says Charlie, his hands hovering over the controller of his game, "but after that I got used to it."

Jenna pulled herself together and stopped drinking, although she still liked a smoke. Then came the holiday for both of them – and a 'no cigarettes' rule. She cried the first night because she wanted a fag and wanted to know whether Charlie was OK. The next morning, she was taken to see him. Charlie looked at her, mystified. "What are you doing here?" he asked. Hazel smiles at the story. "The holiday allowed Jenna to be a wean again."

ThAT holiday camp pilot project offered 12 Scottish children like Jenna and Charlie a holiday. Last year, that figure had risen to 42. Bookings have just begun for next year's holidays and Scripture Union hopes numbers will increase again. They considered running a holiday specifically for children with parents in prison, but realised it was better that the children attended "normal" holidays with other kids.

"It's important that they get away somewhere where there's no stigma attached," says SU holidays manager, Ewen Cunningham. "The fact that imprisonment is part of their set-up is known only by one or two key people. None of the other youngsters know, whereas at school they all know."

Jenna was bullied at school even before her mum got into trouble. Afterwards, it spiralled. "Only one or two people stood by me," she says. "But that's life." The harassment only stopped when she lost her temper, answering back. She was never bothered again.

In January, Jenna will begin her leadership training. She comfort-ate while Hazel was in prison, put on weight and can't believe the physical challenges Lendrick Muir made her face, but even more important were the emotional challenges. The holiday made her face reality, just as prison had made Hazel face responsibility.

"I know it's a bit sad to say this," acknowledges Hazel, "but all this has brought us closer. I wouldn't recommend it to anyone, and the consequences will be with me for the rest of my life, but I do feel it made me grow up and take notice of what is really important."

Charlie watches his screen intently. Jenna listens quietly. You can sense the invisible ties between the three that even prison did not sever.

"We have come through the other side," continues Hazel, "and sometimes I had my doubts that we would."

Names have been changed