A dying woman whose children are in foster care has been told that her contact with them will be cut to 90 minutes a fortnight because of her failing health.

The mother suffers from a brain disorder that means she may have only a few years to live. Her son and daughter were taken into care because of an allegation — dismissed after an investigation — that a friend had sexually abused one of them.

Kate Brown — not her real name, for legal reasons — had already been struggling to make the most of the seven hours’ access a fortnight she had to her children. Last month social services told her this would be cut.

She believes that the new restrictions will squander what time she has left with Louise, 12, and Bill, 10. “By the time they get here, it is already time for them to go,” she said.

Her sister, Anne, said: “They should be upping it. We don’t know how long she’s going to be here.”

Mrs Brown’s large and supportive family have made numerous attempts to bring the children back into their care.

Her father, George, 72, a former BBC executive, was judged too old to look after the children, although he has regularly taken them on holidays. Anne offered to buy a bigger house to accommodate them, but was told that her job as a journalist would make it impossible for her to parent them.

Mrs Brown’s son Sam, who is 23, was assessed as not having a sufficiently stable relationship with his girlfriend. “I feel bitter about the unfairness of the legal system and the way in which social services have behaved throughout this whole sorry period,” George said. The children have lived with five foster families in three years.

Mrs Brown, who used to work as a nursery nurse, has learning difficulties. She was also an alcoholic, and went into rehab before Louise and Bill were born. Though the family insists that since then she has not drunk anything more than a glass of wine at Christmas, both children were placed under a care order at birth.

Her family lived close by and were heavily involved in supporting her in bringing up her children. In 2005 Kate’s sister and father bought her a house nearby. Social services began an assessment with a view to discharging the care order. Then in March 2006 Mrs Brown arrived at the children’s school to find that they had been taken into care. Louise had told her teacher that a friend of her mother had abused her.

Mrs Brown recalled packing her children’s clothes as they waited outside in the social worker’s car. They left that afternoon.

After a police investigation and medical examination, the allegation was dismissed. Louise retracted her statement to the family. But social services became concerned about Mrs Brown’s ability to protect her children.

“The social workers say they have got new families. But we are their family,” Anne said. “When they’re 16 social services won’t want to know them.”

On the brink of adolescence, the children are not likely candidates for adoption and the family says their behaviour has deteriorated significantly. Both hover on the edge of exclusion from school. Their family concedes that they are now difficult to handle together.

Their grandfather believes that this is because of the disruptions: “They have been knocked off a normal way of life with their mother and among family and they have been isolated and pitched into an alien atmosphere.” The City Council stated: “This case is going through an official process and we are unable to comment.”

In 2007 a judge emphasised the importance of retaining the children’s strong family bonds. Anne believes that depriving a dying woman of her children goes against this direction. As her relatives spoke, Mrs Brown faintly echoed their feelings. “Angry,” she muttered. “Angry and sad.”

All names have been changed to protect the identity of the children

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