The former wife of an ex-Battle police sergeant has been arrested on suspicion of murder, following the death of the couple's seriously ill daughter.
Officers were called to the Stonegate home of 31-year-old ME sufferer Lynn Gilderdale at 8.30am on Thursday.
A 54-year-old woman, believed to be Lynn's mother and carer Kay, was arrested on suspicion of murder and has been released on police bail until March 6.
Lynn is the daughter of Richard Gilderdale, who used to be the sergeant at Battle, and now works for Sussex Police as a civilian at Hastings.
She was diagnosed with ME (myalgic encephalomyelitis) in May 1992, and spent much of her life unable to leave her bed, communicating with her family through sign language.
In a media interview two years ago, Kay revealed how doctors at a specialist clinic in London treated her daughter as an attention seeker, with a made-up illness.
She said that although Lynn could not swallow, spoke only in a whisper and failed to recognise people, she was made to undergo punishing experiments.
Lynn's parents decided to care for their daughter at home.
At her worst, Lynn could only move her little finger, failed to recognise anybody, remember anything, experienced painful muscular spasms and shook all over.
She could not bear any light, touch or noise and could hear only one whispered voice at a time.
Lynn, who has a brother Steve, was on lots of drugs to relieve the symptoms of her ME.
She slept for 16 hours a day and never went outside except to hospital.
As a result of being bedridden, Lynn often had blood clots and suffered from severe osteoporosis, irritable bowel syndrome and asthma and was fed through a tube.
She spent two months on a life-support machine at Kings Hospital in London after suffering a punctured lung after complications receiving medication through a Hickman line.
Richard and Kay Gilderdale split up because of unrelated problems, but he visited his daughter regularly and also looked after her.
There is no known cure for ME and Kay previously told how she was online everyday keeping up-to-date with research into the syndrome.
Ch Insp Heather Keating, the Rother district police commander, said: "This is a very tragic incident, but we are not looking for anyone else in connection with it."
The investigation into Lynn Gilderdale's death is being led by Det Ch Insp Andy Griffiths from the Major Crime Branch.