A family has criticised social services after the deaths of an elderly couple.
An inquest will be held on Wednesday for Margaret Mayer, 85, who had dementia. Her husband Angus, 86, was arrested for her murder.
Mr Mayer was hit by a train at Cardiff Central on the day his wife’s body was found in July 2016 and he died seven weeks later.
The council said it sympathised deeply but could not comment further ahead of the inquest.
The couple from Cardiff had six children, who said social services’ response to the care needs of the couple was “inadequate and not fit for purpose”.
The family said their father was not able to cope with caring for Mrs Mayer, who had Alzheimer’s disease, and they “fear for all the families that are struggling with dementia”.
They have written to social services detailing their concerns about the help their parents received.
One son, Andy Mayer, a BBC Midlands cameraman, said in the letter that he had been “extremely worried” about his father’s behaviour and his “inability to cope with caring for my mother”.
Mr Mayer said his father would lose his temper at night in particular with his mother when he “flew into a rage”.
There were meetings with social services, but the problems continued despite day centre visits for Mrs Mayer, and a bed alarm.
The letter asked social services if they had a “duty of care” to Mrs Mayer, and if the department’s response to elderly carers was “too passive”.
The children said their father “wanted to enjoy independent living, but caught in the fog of fatigue… he gave up”.
The letter says that the family will never know if Mr and Mrs Mayer would be alive today if more had been done.
An inquest for Mr Mayer will be held at a later date.