A 25-year-old woman will remain behind bars following allegations she decapitated her mother in their western Sydney home.

Jessica Camilleri was charged with murder after her mother, Rita, was found dead in their St Clair home on Saturday night.

The 25-year-old’s matter was briefly mentioned in Penrith local court on Monday after she was assessed in hospital overnight.

Camilleri did not apply for bail and it was formally refused.

The matter will next be heard on 9 August at the same court where an application will be made for a forensic procedure to be carried out.

It will then be brought back to the same court on 20 September for mention.

Detective superintendent Brett McFadden on Sunday alleged the mother and daughter had been arguing before the dispute turned violent, with neighbours raising the alarm.

He said a number of knives were used in the “horrific” attack on the 57-year-old.

Police have not confirmed media reports that the victim was decapitated.

A four-year-old boy in the house was treated at Westmead children’s hospital for a minor head injury.

Camilleri, who faced Parramatta bail court via video link on Sunday, said she suffered from a number of conditions including border autism, bipolar disorder and anxiety.

She told the court she could not move her fingers properly after “the incident” and had not been able to wash herself properly in the shower to get all the blood off.