A coroner has recorded a verdict of unlawful killing on a ten year old boy who died following a house fire near Newquay.
Ben Philpotts died in the blaze at his home at Trevarrian in January 2010. His mother Patricia, who was 44, also died in the fire. An open verdict was recorded on Mrs Philpotts.
It's believed the fire was started by Harold Philpotts, the estranged husband of Mrs Philpotts, who had a history of mental illness.
He died from burns in hospital a few days after the fire.
His family say Mrs Philpotts and her son were not given enough help and support. They believe the mental health services downplayed the level of Mr Philpotts' illness.
The family say that unless procedures to deal with cases like Mr Philpotts are improved, there will be similar tragedies.
The coroner admitted at the inquest that the reasons behind the fire will never be known.
The schoolboy had been bludgeoned with a sledgehammer, which rendered him unconscious as a fire took hold in Mrs Philpotts' bedroom on the first floor of the dormer bungalow the pair shared with the boy's grandmother and cousin.
Mr Philpotts, who had a history of mental illness and chaotic behaviour, had been staying at the home over the weekend and was thought to have been reluctant to return to his home in Redruth, having been estranged from his wife.
Mr Philpotts, 47, was the prime suspect for causing the blaze, but he died in hospital eight days later having been arrested by police in a field 100 yards from the fire he sought to flee.
Ben was pronounced dead at Royal Cornwall Hospital shortly after the fire took hold, while his mother died at the scene.
Cornwall Coroner Dr Emma Carlyon recorded open verdicts in the deaths of Mr and Mrs Philpotts, and unlawful killing in the case of their son, who had suffered severe facial injuries but was still breathing when smoke filled his bedroom. A sledgehammer weighing 7.4kg was found in the boy's bed.
Dr Carlyon told the hearing in Truro the circumstantial evidence pointed to Mr Philpotts dousing his wife's bedroom in accelerant, after petrol cans were found in the room and a lighter later recovered from his trouser pocket.
But she said there was "no evidence to how the fire was started", and acknowledged testimony given in court from mental health professionals which said the deaths could not have been avoided.
Mr Philpotts had a history of mental illness, having previously been sectioned. He was convinced medics and members of his family were plotting to kill him. He also travelled to various hospitals to get repeatedly tested for HIV following an affair several years earlier. He refused to believe his test was negative following the onset of mental health problems two-and-a-half years earlier.