A woman who lied to police to help cover up the bashing death of 16-year-old Jason Galleghan has made a tearful apology to the teen's family.
Several others have been charged over the incident that left Jason with such serious injuries he died in hospital two days later.
Stacey Pale pleaded guilty to assisting grievous bodily harm with intent.
In a statement read by Pale to Parramatta District Court on Thursday, the 38-year-old said she is sorry to Jason's family.
"Today I'm here to apologise … for what happened to Jason," Pale told the court.
"I'm here to apologise for the loss of a son, and a brother to Jason's sisters."
Psychiatrist Stewart Einfeld told the court in his view Pale has an intellectual disability inhibiting her ability to tell right from wrong.
"When it comes to confronting and understanding circumstances that are more complex, she doesn't function independently," Professor Einfeld said.
He also said she was under the "delusion" she was pregnant at the time of the alleged bashing, which she was not.
"I think she has probably indulged in fantasies that have filled parts of her life she thought were deficient," he said.
Pale's father George also made an emotional statement in which he apologised for Jason's death, saying he wondered if he had failed as a parent.
"I know for his mum, saying sorry will never give her the comfort that she needs," he said.
"But for me and my wife, friends and family, we just want to say we're very very sorry for your loss."
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