A girl whose skin is so fragile her clothes have to be changed eight times a day has been diagnosed with a condition so rare doctors believe she is unique in the world.
Doctors say Madison Hunt, five, has a one in seven billion DNA abnormality - and it could now be named after her.
Madison suffers a range of symptoms including epilepsy, autism and double-joinetd, hypermobile limbs. Her brain has only developed to that of an eight month-old baby.
Until now, doctors were baffled as to what was causing her condition, but experts at London's Great Ormond Street Hospital eventually identified an abnormality with the nineteenth chromosome of Madison's DNA.
Her mum Kelly, 32, from Basildon, Essex, told The Mirror: "She's not even one in a million, she's one in the whole world - one in seven billion.
"It has crossed my mind that the worst could happen and she could die but I'm not going to let myself think about it.
"We just have to enjoy Maddy and make the most of her while we have her. When you brush her hair or touch her, it's like having razors brushed over your skin.
"But she's an amazing little girl, I don't know how she does it. I wouldn't be without her, I'm so proud to be her mum.
"It must be so difficult for her, not being able to understand anything that's going on. It's like being put in another country where you don't understand anyone who is talking to you."
Despite celebrating her fifth birthday last May, Madison is still in nappies and her parents Kelly and Mark have no way of properly communicating with her.
They can cuddle her but her ultra-sensitive skin means prolonged contact with fabric leads to painful rashes developing on her body.
Kelly said: "I realised there was something wrong with Madison when she was about two or three weeks old. She wasn't doing the things she should have been in terms of her movement and awareness.
"It was not until she got to 12 months that doctors realised she had hyper mobile limbs. This means she is double jointed and her muscles take more time to form.
"Doctors have checked all the databases all around the world to see if there's anyone slightly similar to Madison to help us understand more about her. But so far they've not found anyone and we just have to live day to day."
Madison is not the only disabled child cared for by Kelly and Mark, 33.
Her older sister, Bethany, ten, has arthritis and learning difficulties. The couple also have a another daughter, three-year-old Lola.
Kelly added: "It is very challenging having two disabled daughters. I've not had a proper night's sleep for ten years.
"I suffer from stress and my husband had to quit his job as a chef and take two cleaning jobs to support us.
"But I would not swap my girls for the world."
Kelly and Mark are now desperately trying to raise £5,000 to build a sensory room for Madison.