Teenager charged with mother's murder, sister's attempted murder in Perth family violence case

A 16-year-old boy has been charged with murdering his mother and attempting to kill his sister in what police are describing as an alleged "family violence homicide" in Perth's south-east.

The boy's mother, 35, was found dead in the family home in Bentley about 6:15am yesterday.

Police say his 12-year-old sister managed to escape and was found a short time later with "very serious injuries" about 600 metres away on Albany Highway in Cannington.

It is alleged the boy stabbed his mother and younger sister, and he is due to face Perth Children's Court today after being arrested at the home.

The ABC is unable to identify the accused or his alleged victims for legal reasons.

"While the investigation remains in its early stages, police are investigating this as a suspected family violence homicide and homicide squad have carriage,” WA Police Detective Acting Inspector Jessica Securo said yesterday.

She said police would also examine any past interactions the family had with police.

WA Police Commissioner Col Blanch said today the 12-year-old girl was receiving care in hospital for her "very serious injuries".

"[There are] a number of stab wounds," he told 102.5 ABC Perth.

"She is being well looked after and [is] surrounded by family."

Accused 'failed' by authorities

One of WA's leading advocates for vulnerable children said the 16-year-old was "failed" by authorities.

"Australia must ask what happened before the catastrophic violence," youth justice expert and advocate Gerry Georgatos said.

"The boy had 'early intervention' bells ringing loud, but services turned away."

Mr Georgatos said the family lived in "crushing poverty", had insecure housing and "profound unmet needs".

"The family had repeatedly reached out for assistance, yet no sustained, intensive support surrounded them.

"Those circumstances must now be independently investigated — not presumed, concealed, or allowed to disappear when the news cycle moves on."

Mr Blanch described the 16-year-old boy as "known to police" and said the case "couldn't be any more tragic".

"This is the worst case scenario of what can happen when that support [for adolescent violence] is not immediately available," he said.

"No doubt the community will want to know exactly what happened leading up to this event."

'I can only empathise': Commissioner

Speaking generally, Mr Blanch said there had been an increase in adolescent violence in the family home in WA.

"Many of those do involve not just intimate partners, but in fact children against their parents," he said.

Mr Blanch said violence of children against their parents was "significantly under-reported" because "parents understandably are reluctant to report crimes against their children".

"They know police are going to come, it may become violent, it will put their children through the justice system," he said.

"I can only empathise [with] families going through this situation today, who are seeking help and are really struggling with children who either have mental illnesses or are substance abusers or are really struggling to live life.

Premier Roger Cook described the incident as "deeply distressing".

"It would be distressing for the families and friends involved, for the people who live in that community and the first responders," he said.

"So our hearts go out to everyone that's been touched by this horrible incident."

Mr Cook would not be drawn on whether the boy had contact with child protection or youth justice systems.

"We are confident with our child protection system, it's an important part of ensuring we keep our young people safe," he said.

"We will, obviously, always take the opportunity to learn from experiences. Whether this is part of that experience, I don't know."