William McLaughlin choked 35 year-old Mark later claiming his son was “just existing”.

A judge heard Mark feared his dad was going to “crush his windpipe” during the incident at their flat in Paisley, Renfrewshire.

But, he managed to push McLaughlin off and told him: “I don't want to die.”

The 59 year-old, of Nethergreen Crescent, Renfrew, was later held for the attack having earlier admitted he had been at a “low ebb” at the time.

McLaughlin is now behind bars after he pled guilty to assaulting his son to the danger of his life.

He faces a lengthy jail-term when he is sentenced next month.

The High Court in Glasgow heard how Mark McLaughlin had been diagnosed with schizophrenia and was described as a “vulnerable adult”.

On August 27 this year, he was lying on his bed using his laptop when his dad returned home.

After shouting at his son, McLaughlin then “without warning” jumped on top of him.

He straddled Mark and pressed his thumbs down on his neck with force.

Prosecutor Shirley McKenna said: “He tried, but did not get his hands around his son's neck.

“Mark thought his father was trying to crush his windpipe.”

During a struggle, McLaughlin told his son: “It's time for you to die.”

But, Mark managed to reply: “Why don't you just go and kill yourself – I don't want to die.”

Mark was then able to lash out ending the attack. McLaughin became upset as Mark escaped from the flat.

The son initially told two people what had happened – but said he did not want to get his dad into trouble.

McLaughlin meantime called his ex-wife – Mark's mother – and admitted he had tried to kill him before slashing his own wrist.

Miss McKenna said: “He told her that he wanted to kill himself, end his life and Mark's because of his illness, but that he could not do it to him.”

Dad-of-three McLaughlin later spoke with his former wife again and claimed he had been at his “lowest ebb in his life”.

Mark was found by police at his mum's home in Newton Mearns. East Renfrewshire.

The court heard McLaughlin had been suffering from his own personal troubles at the time, but that he did not have a mental disorder.

He admitted to police: “I was totally with the thoughts of me and Mark going away because my son had schizophrenia and is just existing.

“I'm not doing too good either. With all the problems recently – which his mum is really stressed about – I thought it would be better if the two of us just went.”

The court was also told that McLaughlin had been drinking that night and his attack was related to him being intoxicated.

Judge Lord Turnbull remanded McLaughlin in custody and deferred sentencing for reports.