A coroner is demanding to know why schoolchildren are being left to care for sick relatives after a 13-year-old girl died from an overdose of the morphine prescribed for her terminally ill mother.

The plight of child carers came to light during an inquest into the death of Deanne Asamoah, who had been looking after her mother who had been ill for four years.

Deanne fell into a coma after swallowing seven morphine tablets three days after her 13th birthday. The tablets were stored on top of a kitchen cabinet and her mother had made it clear that she was not to touch them.

Paramedics found that Deanne was unconscious and not breathing. Doctors placed her on a life-support machine but it was switched off after tests revealed that she was brain dead.

Thomas Osborne, the deputy coroner for Milton Keynes, recorded a narrative verdict and said that the tragedy was “a cry for attention”.

He said that he would write to Beverley Hughes, the Children’s Minister, asking why it was that hundreds of young people were struggling to cope with such heavy responsibilities, and called for a proper inquiry into the issue.

The inquest was told that there were at least 750 other children of a similar age caring for sick relatives in the Milton Keynes area. Barnardo’s, the children’s charity, estimates that there are as many 175,000 young carers nationally.

Trudi Addai-Twumasi, the girl’s mother, said her daughter had been forced to care for her because her chemotherapy treatment was so debilitating.

She told the inquest that she was unaware of anything troubling her daughter, the youngest of her four children, other than her usual concerns for the illness and what would happen when she died. In the last year Deanne had joined a local support group for young carers.

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