A mum kept her healthy daughter in a wheelchair for six years with false medical claims.
The 12-year-old, who has not been named, was subject to medical treatment that was not needed, and she was sent to school in a wheelchair.
She "suffered significant harm" due to her mum's "exaggeration of her behaviours and symptoms," a High Court heard.
The schoolgirl was also given medication she did not need, and would not have been prescribed without the false claims.
Mrs Justice Judd said the girl had been subjected to "excessive investigations and assessments".
She was also given a drug which could have affected her eyesight - and suffered severe disruption to her schooling.
The judge said the girl had temporarily moved to live with relatives some months ago but decisions about her long-term care have yet to be taken.
She said the girl could not be identified and has not named the council involved.
Specialists had begun to question the "various diagnoses" the girl "appeared to have had" in 2018, the judge said.
The youngster had subsequently left home and spent several months being assessed at a specialist unit, a child protection inquiry had started and council social services bosses had begun family court litigation.
Council bosses argued that between 2011 and 2018 the woman had given medics "an exaggerated or wrong account" of the girl's health and behaviour.
They said the woman had "perpetuated the notion" that the girl had "uncontrolled epilepsy and autism", plus a number of other diseases.
The woman denied the allegations but Mrs Justice Judd ruled against her in a private hearing.
She said the woman had been presenting her daughter to the world as a disabled child with a life-limiting condition, who needed a wheelchair, a special school, a specialist diet and, at one point, artificial feeding.
But she said the picture changed after the girl was separated from her mother.
"It became rapidly clear that she is very much a normal child," said Mrs Justice Judd.
"She does not have a diagnosis of active epilepsy. She does not have any traits of autism. She is physically quite normal and energetic."
Mrs Justice Judd said the girl had suffered seizures when very young and lawyers argued that her mother had a "legitimate anxiety".
The judge accepted that the woman would have been very worried and agreed that those worries might have led her to "over-interpret".
But she said the woman's behaviour had gone "far beyond" what was reasonable.
"I cannot say at this point what was driving the mother to portray her child as having so many problems - whether it was a distorted belief system prompted by anxiety, a yearning for help in some way or another, a manifestation of more widespread distress or something else entirely," said the judge.
"This is something which will fall to be assessed."
The judge made the ruling after examining evidence at a private hearing in the Family Division of the High Court in London in October and published her ruling online.