Two teenage children from Sussex have been taken from the care of their parents after council social services staff told a family court judge of concerns about their weight.

Judge Gillian Ellis ruled the youngsters should go into long-term foster care - and described the case as "very sad and unusual".

West Sussex County Council has responsibility for the children's welfare and previously provided Fitbits and paid for gym memberships for the pair.

The family has also been involved with Weight Watchers.

But Judge Ellis said that, months after family court proceedings began, there had been no reduction in the children's weight.

The judge said the children's parents had not seemed to understand "the seriousness" of concerns raised by social services staff and had failed to "set boundaries" or "promote healthy eating and exercise".

She said the children needed the chance to "learn ways of living more healthily" and to "improve their health by losing weight".

Detail of the case emerged in a ruling by Judge Ellis published online on Wednesday.

The judge had considered evidence at a private family court hearing in Sussex late in 2020.

She said the family could not be identified in media reports of the case.

Judge Ellis said West Sussex County Council was the local authority involved.

The judge said there were also concerns about poor home conditions and a lack of guidance on personal care.

"Everyone agrees that this is a very sad and unusual case, of a loving family, where the parents meet many of the basic needs of the children, but the local authority has been concerned that the parents are not meeting the children's health needs, in that both children are severely overweight, and the parents have shown an inability to help the children manage this condition," the judge said in her ruling.

"The case was such an unusual one because the children had clearly had some very good parenting, as they were polite, bright, and engaging."

Judge Ellis added: "The parents did not seem to understand the seriousness of the local authority concerns.

"They failed to set boundaries for the children, or to promote healthy eating and exercise."

She went on: "The children had failed to engage consistently in exercise despite the local authority providing Fitbits and paying for gym memberships.

"The children were supposed to provide recordings from their Fitbits but this had not been done.

"The mother blamed lockdown for the inability to exercise but exercise could still be taken in the home or by walking outside.

"The attendance of the family at Weight Watchers had been inconsistent."