A judge has warned of the exceptional harm caused to children who are manipulated by warring parents.
Mrs Justice Parker said that it not only distorted the relationship of the child with the parent but also the outside world as children who were suborned into flouting court orders were given extremely damaging messages about the extent to which authority could be disregarded.
The judge said she was disappointed that the professionals in the case of three brothers, who cannot be identified, were unable to understand that message.
The social worker and guardian appointed by the court had asked her not to intervene over contact with the father but allow the boys to stay with the mother as they wished.
At London's High Court today, she said: "Parents who obstruct the relationship with either mother or father are inflicting untold damage on their children and it's about time the professionals truly understood this."
She said that they had not taken into account the degree of parental manipulation in the case and the danger represented to the younger children from the inappropriate power given by the mother to their 15-year-old brother.
"I am in no doubt that he feels he needs to fight his mother's corner on contact. I don't think that he is developing as he should under her influence and in her home. I cannot trust him to co-operate and I think it's doing him harm.
"At his age, he should be regarding both of his parents as out of touch and useless - rather than siding with one against the other.
"The extent to which he has become a knight in shining armour for his mother is truly concerning."
The judge said that the couple, who married in the mid-90s, were both intelligent and articulate but their inconsistent parenting had led to the eldest boy sometimes showing extraordinarily violent behaviour. He was the "carrier for the toxic emotions in this family".
Earlier this year, the mother had gone to a refuge and the local authority had uncritically accepted her allegations of violence against the father, ignoring his evidence which showed that she was very emotionally troubled.
The mother had herself shown physical violence to the children and had inappropriately allowed her eldest son to become her confidante and to discipline his brothers, to whom he had sent "disturbing" texts urging them to resist contact.
The judge said that the Children Act referred to the "ascertainable" wishes and feelings of a child which meant the court had to look at actions rather than words.
"It is my view that the ascertainable wishes and feelings of these boys have been demonstrated. They are more than happy to be with their father and may feel some relief being out of the maelstrom."
She added: "I regard parental manipulation of children, of which I distressingly see an enormous amount, as exceptionally harmful."
She was in no doubt that the mother's track record was such that she could not currently have contact with the two younger boys.
"Much as I would like to give these boys Christmas as they believe they want it, it is unsafe for them to spend Christmas Day with their mother and her family."
She said she w as in no doubt that they should live with their father until the case returned to court, while the older boy should live with his grandmother and only see his mother under supervision.
She was not suggesting that the father was an "angel" but he was genuinely concerned for the boys, had a more objective view of what was in their interests, and far more empathy than the mother
She commented: "I take domestic violence extremely seriously, It is a terrible social evil when it exists. But not all allegations of domestic violence and abuse are true and at the end of a stormy and difficult marriage as this has been betwen the parents of the children, it is very easy for parents to re-write history in their own minds."