Up to 600 children, some as young as seven are leading lives as transsexuals after being identified as having a rare psychological condition. All are being counselled until they can have sex-change operations in their late teens.
The youngsters have gender dysphoria - the medical term for profound confusion about sexual identity. They lead lives in direct contradiction to their biological sex. Most cross-dress at school and at home and some even change their name by deed poll
Psychiatrists report the numbers of these children are rising every year as recognition and awareness of the condition increases.
Adam, a seven-year-old who agreed with his mother to talk to The Express on Sunday, wears girls' clothes and calls himself Sarah.
Asked why he wants to be a girl, he said: "Because I already am one. I was damaged before I was born inside Mummy's tummy, so I was born into a boy's body. I'm never going to be a man. I'm going to grow up into a woman."
His mother Louise said: "He began showing signs of wanting to be a girl when he was three. I remember feeling very scared. I couldn't understand it. He made himself look just like a little girl and it wasn't right."
"Of course I questioned myself, wondering what I might have done. Now, after four years of learning about his condition, I can't say 'I'll only love you if...' It just doesn't work like that. He's an innocent child acting in a way that comes completely naturally to him."
James, 11, officially changed his name from Janet this summer, when his parents agreed for the first time to call him "He". His mother Maria tolerated his behaviour until finally being told by a psychiatrist: "Your daughter is among a small group of people who emotionally feel they belong to the opposite sex."
"It killed me," said Maria. "She was saying the words and I was just thinking 'Please don't let this be true'. The game was over then. That's when my husband and I knew we had to face up to it."
James said: "I'm a boy, I was born trapped in the wrong body. Sometimes I get bullied at school. And if they say, 'you're a girl', I tell them, 'Oh no! I left my high heels behind!' I know I'm slightly different, but the doctors won't tell me when I can start treatment."
Both James and Adam are well-educated, articulate and come from stable families. They have been with the self-help group Mermaids.
Spokeswoman Margaret Griffiths, whose own son had a sex change at 18, said: "Of course, people react with disbelief. But frankly, until you've been there, you just don't know what it's like. Parents get told they shouldn't be letting children do this, that it's all their fault."
"But the parents aren't a bunch of hippies who let their children get away with anything. They are normal people who have learned to cope, often after years of heartache."
The Royal College of Psychiatrists has drawn up new guidelines for dealing with the condition, encouraging increased support and early counselling.
Gender dysphoria can become obvious in children as young as three, some experts claim.
They say that the youngsters begin to reject toys and clothes traditionally associated with their biological sex and, as they grow older, find it traumatic to be made to "go along" with their anxious parents' wishes.
Their schoolwork deteriorates. The children can become withdrawn and even show suicidal tendencies. Most are desparate to have hormone treatment but they must wait until they are past puberty.
Specialists say a child risks abnormally thin bones if hormones are given earlier. Surgery is out until at least 18.
Bernadette Wren, of the Gender Identity Development Unit at London's Portman Clinic, which has dealt with dozens of child cases, said: "We try to prevent secondary problems - that is huge anxiety, depression, teasing at school, children so occupied with their worries about gender that they can't learn."
Dr. Caroline Brain, a paediatric consultant said: "At that young age it is not the right time emotionally for anyone to come to such a dramatic decision."
The recent release of a new French film, Ma Vie En Rose - the story of a little boy who wants to be a girl - is likely to heighten the debate.
ADAM, seven, likes to be called Sarah. Here his mother, Louise, reveals how their pain eased.
It was four years ago that Adam's condition first began to show. Until then he had occasionally tied tea-towels round his waist like a skirt or wrapped himself in the net curtains as though it was a wedding dress, but I just dismissed it as a child playing.
Then, on that particular day, I went up to his room. He had pinned flowers all around his bed and was sitting on it wearing one of my dresses and my make-up. I just turned cold. I told him to take everything off and said he was never to do it again.
I cried my eyes out. I spoke to my husband, Adam's stepfather about ti and I just thought that we'd get him into normal boys' things. But everything we did was pointless.
He was getting more concerned with how he looked in the mirror and how his hair was. He wanted a doll, but we gave him a teddy instead. He just wrapped it up like a baby.
We would tell him, 'you'll never be a girl, you're a boy and you'll grow up to be a man'. Then he would break down and scream hysterically. I was just dying inside.
Once we found a huge poster he had made hidden under his bed. It said, 'God made me wrong'. And every morning when he woke up, still a little boy, he would cry his eyes out. It was unbearable. He refused to do any school work, constantly complaining that he felt 'too much like a boy'.
Then I found out more about his situation and broke down. I realised I wasn't alone. Finally I bought him female shoes, socks and cardigan. Overnight, he changed - his schoolwork became excellent and at home he felt happier than he had been for months.
We saw a child psychiatrist and then a hormone specialist. Adam immediately asked for a 'special pill' to help him. Of course he's not allowed anything at his age.
At school, he uses the boys' lavatory but does so during lessons by special dispensation.
He likes to call himself Sarah, but we do not use that name. We still call him Adam.
Now we have good days and bad days. Of course, I get very depressed. It's quite a thing to have a son who effectively has become your daughter. But I have to show unconditional love.
JANET, 11, has changed her name by deed poll to James. Here her mother Maria tells their story.
MY DAUGHTER announced herself to be male even when she was stringing her first words together. We now call her James and refer to her as a boy. At first, of course, we didn't know what to think. We bought him girls' toys, but he destroyed every doll we gave him. When he was four, we took him to a GP who had no idea what to do. She told us to come back in six months "to see if anything had improved". It didn't.
When James started school he detested his girl's uniform, so I let him wear the school's unisex option of a tracksuit. He struggled along until he was seven and proper school uniforms had to be worn. The teachers called me in, concerned that I was letting him wear boyish things.
They told me I was encouraging him, that he would end up depressed and might commit suicide when he was older. They had no experience of what he would do if I attempted to put him in girls' clothes.
We went back to the GP and were referred to a psychiatrist, who told us he was one of very few children who felt they were the wrong sex. It was an awful time. I remember Jim, my husband, saying he wanted to kill all cross-dressers - but it was only an outburst, an attempt to express the pain. Now he is as supportive as I am.
I had always thought of cross-dressers as sexually perverted, I thought, 'Have I got some kind of freak here?' Friends told me I was soft in allowing James to wear boys' clothes, but I could hardly slap him every morning.
Now we attend counselling sessions and in summer his name was changed by deed poll so he would have a male name on the school register. That's when we made the decision to call him 'He' for the first time. I thought, that's it, I really have lost my girl. But being called 'She' upset him so much.
There have been sad times. At one stage he had few friends, and stayed inside at break to avoid being on his own in the playground. Things have slightly improved now, although he still uses the medical suite to change for sports and go to the lavatory.
I used to say to him, 'Why can't you go along with it all, make less trouble for yourself?', but he would look sad and say, 'I don't know Mum, but I can't.'
All names and identities have been changed. Families seeking further information should contact BM Mermaids, London. WC1N 3XX