A Sydney woman charged with the stabbing murder of her father and sister has pleaded not guilty due to mental illness.
The 26-year-old woman, who cannot be named for legal reasons, is charged with murdering her father and younger sister at their Revesby home in Sydney's south-west in July 2007.
She has also pleaded not guilty to a charge of inflicting grievous bodily harm with intent to murder her mother.
The court previously heard the woman was diagnosed with a mental illness but refused to take medication because of her parents' belief in Scientology.
Justice Grove has ordered the woman be kept in a medium security unit at Long Bay jail.
He will make a judgement on the matter next week.