A 19-year-old man has been charged with the murders of a mother and her two children in Ellenbrook.
Police attended a home on The Broadway in the early hours of Sunday morning.
The bodies of an eight-year-old boy and a 15-year-old girl were found inside the home, while their 48-year-old mother was located in the backyard suffering from critical injuries.
She was taken to Royal Perth Hospital but died a short time later.
Homicide detectives have since charged a 19-year-old man, who lives at the house with the victims.
He will appear in the Midland Magistrates Court today facing three counts of murder.
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