A Peterborough father "consumed by grief" killed the man he blamed for causing his son's drugs overdose death before taking his own life, an inquest has heard.
Roy Allison, 65, stabbed to death 34-year-old Duncan Bell three months after the sudden death of his son, Roy Jnr.
Three separate inquests at Peterborough Coroner's Court heard how Roy Jnr, with his friends Mr Bell and Grant Maker, had been celebrating his 28th birthday at the home he shared with his father in Hetley, Orton Goldhay, Peterborough.
The trio consumed a mixture of MDMA, a pure form of ecstasy; cocaine; beer, and spirits. The next day, March 21 last year, Roy Jnr was discovered lying alone and lifeless in his bedroom, while Mr Bell and Mr Maker suffered no ill effects. The inquest heard a post-mortem examination found he had died from an ecstasy overdose.
In the months after his son's death, Mr Allison became so convinced that Mr Bell was responsible because the MDMA came from him, that he decided to kill him.
He was found dead at Mr Allison's address on July 1 last year. He had been knocked unconscious and stabbed six times, the blow which killed him had pierced his heart, the inquest heard. The body of Mr Allison was found just hours later hanging in the grounds of Peterborough Crematorium.
Coroner David Heming recorded a verdict of unlawful killing in respect of Mr Bell, and said he was satisfied that Mr Allison had taken his own life and recorded a verdict of misadventure in respect of Roy Jnr.
Speaking outside court, Ms Bell said she was pleased the inquest was over and that it had shown her son was not a drug dealer.
"I'm glad the truth is out," she said. "Duncan was not a drug dealer, he had in the past had a drug problem."
Asked how she felt about Mr Allison, she said: "I forgive him. He's a man that had lost his son, his world had disappeared.
"He was psychotic; he was out of his mind.
"He wanted some kind of justice, he wanted a life for a life, it's just a shame that it was my boy and Grant was very lucky that he never got him."