A 15-year-old girl gasped out: "Tell mum I love her" with her last breath as her brother, a 20-year-old autistic man, strangled her to death, a court has heard.
Amanda Selby was fatally attacked by her brother Matthew Selby after an argument in a caravan at the Ty Mawr Holiday Park in Towyn, near Abergele, North Wales, on Saturday July 31 last year.
Police were called to reports of a "domestic disturbance" at the park before Amanda sadly died at the scene.
At Mold Crown Court on Friday, Selby, who pleaded guilty to manslaughter by diminished responsibility at an earlier hearing, was give an extended sentence of 10 years – made up of a five-year custodial term and five years on extended licence.
The court heard of how Selby overpowered his sister Amanda, 15, strangling her on the floor of her bedroom in the seaside caravan.
The pair, who were "very close", fell out when Amanda bent the pin on a lapel badge belonging to her big brother.
Selby "lunged" at Amanda when she hit him with an electric charger, cutting his lip, Mold Crown Court was told.
The siblings' father Anthony Selby wasn't strong enough to separate his children and Amanda gasped out: "Tell mum I love her" before she stopped breathing.
The court heard Selby had autism and mental health conditions that triggered the attack.
Judge Rhys Rowlands said the extended licence is considered necessary to protect members of the public from the risks posed by Selby.
Passing sentence, the judge said: “The family has been shattered by what happened that day in July last year.”
Prosecutor Jamie Baxter said: "This is a deeply tragic case. Selby has a history of intermittent explosive disorder, violence and autism. He needs help."
Selby, of Ashton-Under-Lyne, Greater Manchester, was jailed for 10 years after admitting manslaughter on the grounds of diminished responsibility.
Judge Rowlands told him: "There was considerable suffering to your sister who was absolutely no match for you and simply unable to defend herself.
"This happened in front of your father who saw his daughter killed and was completely helpless to intervene."
Selby was on a family holiday at the Ty Mawr Caravan Park in Towyn, North Wales, when he caused his sister's death by asphyxiation in July.
A family tribute at the time said: "Amanda was a loving daughter and granddaughter - she was caring, thoughtful, liked to help others and very much loved."
CPS Wales spokesman David Mainstone said after the case: "This was a tragic killing of a teenager. Matthew Selby attacked his sister in an impulsive and aggressive outburst after a series of escalating arguments between them during a family holiday.
"The prosecution case included psychiatric reports which found that Selby's autism, intermittent explosive disorder and major depressive disorder were likely to have triggered his violent actions.
"Our thoughts remain with all those affected in this case."
