Katherine was listed as dead in Burke's Peerage in 1961.The sisters were sent to the Royal Earlswood Hospital at Redhill, a grim Victorian mansion.
He died in 1930, aged 44; Fenella Trefusis died in 1995.
After decades in the Royal Earlswood, Miss Fane and Katherine Bowes Lyon were moved in 1996 when the hospital closed.
For many years, Miss Fane lived in homes with another relative, Katherine Bowes Lyon, also related to the Queen Mother.
The pair both had a mental age of six and were said to be inseparable until their home closed last February and they were split.
She had been very poorly for a long time," she added.
Lord Clinton, Miss Fane's nephew, was unavailable for comment.Waiting to trip up our relationship, if not destroy our marriages.It’s kind of like trying to hold a beach ball under water.That is quite unfair on her and other members of the family.I can say she was properly looked after until the day she died."The decision to move her from Ketwin House did not contribute to her death.For example: sit down and tell your spouse that you need a night a week to yourself; ask for help cooking meals/cleaning/whatever; tell your spouse you need his/her support when it comes to disciplining the kids; ask him/her to hang out with your family instead of spending every weekend golfing/rollerblading/underwater basket weaving, etc.