The sister of a Sydney woman who brutally murdered and decapitated their mother has told a court she was given endless help that she refused.
Jessica Camilleri has been found guilty of manslaughter after Rita Camilleri was stabbed to death in July 2019.
Her sister Kristi Torrisi on Wednesday told the NSW Supreme Court her mother was taken from her by the "selfish hands of my own sister".
"Killed and butchered like she was nothing."
Her family was well aware of the help needed by Camilleri - who has since been diagnosed with a number of mental disorders - but she consistently refused their support, her sister said.
"She preferred the attention her behaviour attracted instead," she said.
"I feel my family have now been accused of not helping her but all we did was try."
The victim's sister Mary Hill also spoke of the "double-edged sword" of grieving her baby sibling but also feeling mixed emotions towards her niece and perpetrator.
She described saving her sister from drowning in a neighbour's dam when they were children.
"But as hard as I tried I couldn't save her from Jess.
"Rita's unconditional love for her daughter was remarkable."
"She was blindsided and couldn't see what I could see."
Ms Hill said her family had been let down on numerous occasions by the mental health services.
"This happened to our family even though Rita did the very best she could. She asked for help," she said.
Camilleri told a psychiatrist she "saw red" when her mother threatened to call emergency services to put her in a mental institution and was in a fit of rage when she began dragging her mother by her hair down a corridor to the kitchen of their St Clair home.
She used seven knives, some of which she broke to inflict more than 100 wounds to her mother's head, and another 100 defensive wounds were found on her body.
Later diagnosed with obsessive compulsive disorder among other conditions, Camilleri had a horror-film obsession which partly inspired the gruesome attack, the court has heard.
She is due to be sentenced in March.
