A son who killed his father after a trivial argument about charging his mobile phone has been jailed for 18 years for manslaughter.

Patrick Murphy was also given nine years for wounding his brother Mark, 34, with intent to cause grievous bodily harm. It will run alongside his manslaughter sentence.

Murphy knifed his father Joe and then plunged a knife into his brother as he tried to intervene in the row at the family home in Hectorage Road, Tonbridge.

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He was also handed a restraining order, stopping him from contacting his family for 15 years.

During the trial the court heard Murphy allegedly threatened his mother Sandra after stabbing his father: “Step back, or else you’re going to get it. I am going to finish him off.”

Murphy, who previously lived in Snodland, claimed he had been bullied for years by his father and stabbed him in a "moment of madness".

The jury previously heard of the family's living arrangements. Murphy and his older brother shared a room and slept in single beds, arranged in an L-shape.

He told the court there was little space, and the majority of items belonged to Mark.

He also said each family member had a designated seat in the living room, beside him.

"I would sit on the stairs or on a container box or I would go upstairs and mind my own business," Murphy added.

Murphy, who attended Paddock Wood Primary School and The Hayesbrook School in Tonbridge, said his father continually ridiculed him, called him names and bullied him, which led him to become a "ticking time-bomb".

Asked by his barrister James Turner QC whether he ever had a girlfriend or crush, Murphy said yes, but the court heard his father found out and humiliated him.

"My dad went down to this charity shop and raided the bins he brought back some knickers he put them in an envelope and through her door, he made it look like it was me, I never saw her again," he added.

Video: CCTV footage shows Patrick Murphy buying alcohol and knives before returning home

Family life in the home was dysfunctional, said Judge Statman. Voices were raised and there was verbal aggression towards Murphy by his father.

“In your mind, you felt humiliated by him,” Judge Statman continued. “Your father was physically an extremely large man.

"It is to be noted he sadly had mental difficulties of his own, as did your mother.

“He had sought in the past to take his own life. There is a recorded act of violence in 2008 perpetrated against you when you ended up in hospital.

“Your father introduced you as a child to alcohol. He expected that the rules of his house were to be obeyed. In old school parlance, he ran a tight ship at home.”

Maidstone Crown Court heard Murphy had bought the knife that inflicted the wounds at Sainsbury’s in the town shortly before the stabbings.

He had also drunk three cans of strong Special Brew lager he bought from an off-licence.

The judge said when Murphy returned home he immediately confronted his 25-stone father in the living room as he sat in a chair.

“You stabbed him through the arm and then inflicted a further, but substantially less serious wound, to his chest,” the judge said.

Mr Murphy got out of his chair and the pair ended up in the back garden. Mark Murphy emerged from the outside lavatory to see his father fighting for his life. His mother was “understandably hysterical”.

Mark reacted instinctively by punching his brother and he was stabbed in the arm.

“Whatever Joe Murphy’s failings were, by your actions your mother has been left without her beloved husband and your brothers and sisters have been deprived of their father.

“In her measured victim personal statement your mother details her profound sense of loss and the impact your offending has had on Mark, and also on the family has a whole” Judge Statman told Murphy.

Mark Murphy was taken to King’s College Hospital in London and treated for wounds to his chest, right arm and hand.

The court heard the key to Murphy’s offending lay in the fact that he and alcohol did not get on. When sober, he led a law-abiding life. When he took drink, he became a different person.

“I am satisfied this is a slow burn of loss of control, following accumulative abuse over the years which steadily built up against the background of mental health frailties I have heard about,” said the judge.

“I deal with it as manslaughter with a loss of control. The tragedy of this case is by your acts you have lost contact with those who have been nearest and dearest to you.

“I am mindful of the fact you have an IQ of 74. I am mindful of what you said to him [Mr Murphy] after the attack: ‘I should have done that years ago."

VIDEO: Detective Chief Inspector Tony Pledger talks about the case.

A woman living next door agreed with a suggestion by Murphy’s QC James Turner that they were “neighbours from hell”.

Prosecutor Philip Bennetts QC said after the argument about charging his phone Murphy stormed out and went to Cash Converters and sold his phone for £20.

He was shown on CCTV footage at the High Street shop just after 5pm. He then went to the Wine Library off-licence and bought four cans of Special Brew.

While doing so, another customer asked him: “Is life that bad having to have such a strong beer?”

He replied: “You don’t know the half of it. I need to drown my sorrows.”

Murphy went to B&Q in Cannon Lane but left after looking at knives there. He went on to Sainsbury's in Angel Lane and bought a pack of three knives.

As he left the store, he pulled the largest knife out of the packaging and returned home at 7.12pm. The attack then happened.

Murphy, who has learning difficulties, claimed in evidence he intended to kill himself in front of his family but lost control during the row.

The jury considered its verdict for a day and a half.