Emma Walton (centre) and Vicky Horgan (right) were very close

Stuart Horgan, 39, from Plaistow, London, who shot his wife in front of her young children, "adored" his family, the inquest heard.

He died while on remand at HMP Woodhill, Bucks, for the double murder.

Vicky Horgan, 27, and her sister Emma Walton, 25, died at a barbecue in Highmoor Cross, Oxon, on 6 June 2004.

On 20 June 2004, Father's Day, Horgan was found dead in his cell after slashing himself with blades broken out of razors given to him by prison staff.

He had been in the jail's segregation unit after being taken off suicide watch four days earlier.

He adored his wife and his children, however there was an extreme side to his character which would be brought out by drink Jayne Sterne, Horgan's sister

He had managed to convince staff he was not a suicide risk.

During his time in prison he had also been detoxing from a 15-pint-a-day alcohol habit.

Horgan's mother, Sandra Horgan, of Pontefract, West Yorkshire, admitted to the jury at the civic offices in Milton Keynes that her son had had a "troubled background".

When asked by the coroner what he was liked she replied: "He was just a typical fella."

At this the coroner remarked: "What, on 15 pints a day?"

Horgan's sister, Jayne Sterne, of Plaistow, told the inquest: "He adored his wife and his children, however there was an extreme side to his character which would be brought out by drink. He was open and honest.

"I never would have believed he could've been capable of what he did."

Horgan died while on remand for the murders at Woodhill Prison

She said her brother had been crying, in low mood and, in her view, "mentally unstable" while on remand.

GP Dr Ralph Drury, who once treated Horgan, said he had a history of drug abuse, domestic violence and depression and had once threatened a partner with a knife.

He said Horgan had followed his father into alcoholism, also using cocaine, ecstasy and cannabis.

The inquest heard how Horgan was expelled from several schools and put into foster care after his parents split up in the 1970s.

The jury had previously been told how Horgan had gunned down his wife and her sister at a family barbecue.

The mother of his victims, Jacqueline Bailey, was also seriously injured in the attack, which took place in front of Ms Horgan's two daughters, aged four and seven - the youngest of whom is Horgan's.