A woman has told a court she couldn't move her fingers or wash the blood off properly after she allegedly decapitated her mother in their western Sydney home.
Jessica Camilleri on Sunday faced Parramatta Bail Court charged with murder after she allegedly attacked her mother Rita in their St Clair home the previous night.
The 25-year-old did not apply for bail, with her lawyer telling the court she had significant health issues.
Magistrate Michael Price made an order for her to be assessed in hospital before her next court appearance.
Camilleri, who appeared via video link, said she couldn't move her fingers properly after "the incident" and hadn't been able to wash herself properly in the shower to get all the blood off.
She told the magistrate she had a number of conditions including border autism, bipolar disorder and anxiety.
Detective Superintendent Brett McFadden previously alleged the mother and daughter had been arguing before it turned violent with neighbours raising the alarm.
AAP understands the mother was decapitated but police won't confirm these reports.
Det Supt McFadden said a number of knives were used in the "horrific" attack on the 57-year-old.
"This is up there with one of the most significant, most horrific scenes police have had to face," Det Supt McFadden told reporters on Sunday.
"There is no stepping away from the fact that this was horrific and a significant attack, and the injuries that the victim suffered were extensive."
A four-year-old boy who was in the house was treated at Westmead Children's Hospital for a minor head injury.
"He is being cared for by his family and getting medical support during the course of the day. The family is distraught as to what has taken place," Det Supt McFadden said.
Meanwhile, neighbours on Sunday were shocked, with one man telling ABC News: "it's terrifying to know that you live so close".
Police say they were aware of the family, but what unfolded on Saturday night was "not foreseeable".
"It is a very difficult, challenging, confronting investigation," Det Supt McFadden said.
Strike Force Comeroy has been set up to investigate the incident and officers at the scene have been offered professional help.
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