Three teenage brothers who developed a "narcissistic cult" mentality and came to believe there was no point leaving home, socialising or going to school, should leave their mother's care, a High Court judge has concluded.
They formed a "group identity" and "saw themselves as intellectually superior and separate to the rest of the world" psychotherapists told Mr Justice Hayden.
Two of the boys spoke to each other in a "language they had devised", the judge heard.
Detail of the case has emerged in a ruling by Mr Justice Hayden after a private hearing in the Family Division of the High Court in London.
The judge said the family involved could not be identified.
He said social services bosses at Wandsworth Council (pictured) in London had responsibility for the boys' welfare and had asked him to make decisions about their futures.
Social workers had raised a series of concerns and said the children had suffered neglect plus physical and emotional harm due to stress, inadequate food and a lack of medical provision.
They said the boys had not had "appropriate" exercise and outdoor activity.
Their mother, who had mental health issues, had "failed" to allow them to attend school, socialise, play outside or take part in activities.
Social services bosses said the boys had come to believe there was "no purpose to attending school, leaving the home or socialising with others".
Two psychotherapists said the brothers had "formed a group identity in which they saw themselves as intellectually superior and separate to the rest of the world".
They said a "cult mentality" had developed. One described it as a "narcissistic cult".
Mr Justice Hayden said he had heard how two of the boys had spoken to each other in a "language that they had devised".
The judge also said he had been told of an achievement and award system operating at the boys' home.
"There was an elaborate and quite rigid structure to their interactions predicated on an achievement and award system," he said.
"Achievement of particular tasks enabled time on the computer or an opportunity to pet and stroke the cat."
Mr Justice Hayden indicated that the boys had been placed in residential care units on a temporary basis pending long-term decisions on their futures.
He said they should stay where they were and not return to their mother's care.
The judge made decisions after analysing legal argument from barristers - Julien Foster, who led the council's legal team, Rachel Gillman, who led the boys' mother's legal team, and Lucy Sprinz, who led the boys' legal team.
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