A mother who convinced doctors that her son was the “sickest child in Britain” is facing jail for falsely claiming £130,000 in disability benefits.

The woman kept her son confined to a wheelchair fitted with oxygen bottles, fed him a deliberately unhealthy diet and allowed him to undergo an unnecessary exploratory operation.

She claimed the boy, now aged 8, had cerebral palsy, cystic fibrosis, the throat disorder dysphagia and was allergic to all types of food. She also doctored his urine samples to make it appear he had diabetes.

He was believed to be so ill that he was singled out for praise by a leading children’s charity and even met Camilla, Duchess of Cornwall, at a charity event. Her lies fooled health professionals as well as the boy’s own father.

Doctors fitted him with a permanent feeding tube so that he could be fed through a food pump he had to wheel around behind him. In six and a half years the child spent at least six weeks of every year in hospital.

The deception, which had earned her £20,000 a year in benefits as well as a Motability car, was finally uncovered after she claimed to have been raped by a stranger, in an attempt to avoid a hospital appointment at which doctors would have discovered the boy was not suffering from diabetes.

Yesterday she admitted one count of cruelty on a person under 16 in which she caused or procured a child to be ill treated, abandoned or exposed in a manner causing unnecessary suffering or injury to health. She also admitted a charge of intending to pervert the course of justice for making a false accusation of rape.

Speaking after the hearing, Detective Constable Mark Uren said: “The investigation began when a doctor who was dealing with the victim came to us with concerns he was being unnecessarily treated.

“She sent him to school in a wheelchair with oxygen, and she paraded him as the sickest child in Britain. She also dressed him in an ill-fitting suit so he appeared to be losing weight.

“His mother used the fabricated illnesses to take free holidays paid for by charities and was introduced to celebrities. She claimed the highest rate of disability living allowance.

“We discovered that he was, in fact, suffering from none of the symptoms of illnesses that she claimed. She was very cunning and aggressive with medical professionals.”

The woman, who had studied briefly to be a nurse, faked the boy’s symptoms so that he believed he was a chronic invalid. He was said to be “mentally traumatised” by his ordeal.

Hospitals including Great Ormond Street treated the boy for the invented illnesses. His school in Devon spent tens of thousands of pounds on wheelchair access for him.

Sometimes the boy defied his mother’s instructions and played with friends. A police source said: “He told his school he could run and play out of his wheelchair. It was like Andy out of Little Britain in his chair and climbing up diving boards at swimming pools.

“He was made out to be the sickest kid in Britain when all the time it was his mum who was the sickest person around.”

Mr Uren said the deception started soon after the boy was born. “Several test were carried out but nothing found. Four years later he had surgery under anaesthetic to install a feeding tube.”

Despite the claims that he was allergic to food including wheat and gluten, a health worker spotted him at a fair eating a burger.

Mr Uren said: “His bedroom at home was like a scene out of TV’s Casualty. There was a specialist bed and his mother wore a nurse’s outfit. There was boxes of unopened pump feed and numerous medications. in there. The feed was unopened because the boy did not need them. We also found video of the boy running up and down a beach on holiday with not a tube in sight.”

Suspicions were also raised when she added glucose to his urine to make him appear diabetic.

The boy’s mother had even wangled an invitation to a recording of the television talent show The X Factor. Mr Uren said: “She contacted Simon Cowell setting out her son’s illnesses and he invited them to a live performance show.”

In June 2007 consultants were seriously questioning the case when the mother then told police that she had been sexually assaulted by a mystery motorcyclist. She deliberately grazed her head and body and rubbed bleach into the wounds to make her story of a violent attack credible. Police spent hundreds of hours investigating the incident. She kept up the pretence until a woman came forward to say she believed her husband was the rapist.

During the investigation the mother had managed to get herself a brand new Motability car claiming she feared the rapist could recognise her old one.

There are three other undisclosed charges, which will be dealt with at sentencing at a date to be fixed. Judge Stephen Wildblood, QC, ordered psychiatric reports to be carried out. At Exeter Crown Court the judge indicated that she will face a maximum jail term of three years and three months.

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