The 48-year-old mother has been confirmed as Michelle Peterson, and her daughter, Bella, 15, and son, Rue, eight, were killed in their family home on Brixton Crescent on Sunday morning.
19-year-old Teancum Vernon Peterson-Crofts, who is believed to be related to the victims, has been charged with three counts of murder. He appeared in Midland Magistrates Court yesterday but has since been transferred to a Psychiatric facility following a bizarre outburst during his hearing, reports News.com.au.
Family friend Toni Ata took to social media to express her heartbreak at the devastating loss, describing her friend as 'kind, happy' and says she 'loved her kids, all of them unconditionally'.
"Michelle had such a hard life," Ms Ata said.
"She lost two babies years ago when they were babies too: sudden infant death syndrome.”
Ms Ata has also organised a GoFundMe page to raise money to cover funeral costs and to help Ms Peterson's surviving children.
"Shelly was my friend," she wrote on the page. "She was kind, happy, loved her kids, all of them unconditionally."
"At times in her life she was rough. She was flawed, but we all are, no one is perfect and Shell tried. She was always good to me, always supported me, always made me feel like a better person."
The page has since raised over $18,000.
Police entered the property to find the two children dead inside and the mother in a critical condition in the backyard. The woman was taken to Perth hospital but died a short time after.
Assistant Commissioner Paul Steel said the gruesome discovery had shaken his colleagues, reports News.com.au
“A senior homicide squad investigating officer said to me today it is potentially the most horrific crime scenes he has ever been called to.
“They located two deceased people inside the home and a further victim in the rear yard.
“An ambulance was called in relation to the critically injured victim in the rear yard who was conveyed to Royal Perth Hospital and, tragically, she died en route.”
The home and the convenience store are both now crime scenes and it will likely take days for them to be processed.
“This is a terrible tragedy for the family involved, for their extended family and for those first responders who were forced to attend what was a horrific crime scene.
“I can assure the community that WA Police are applying all resources that we can to get to the bottom of what’s happened here.”
A local resident told The West Australian he was woken by screaming and yelling about 1am on Sunday morning.
“I just heard a lot of screaming and yelling and a bit of fighting, and the cops flew past here and headed up this way,” Matthew Schreck said.
“It was real loud yelling and screaming. It sounded pretty bad. It sounded like a man.”
A 19-year-old, who is believed to be related to the victims, has been charged with three counts of murder.
He is due to appear in the Midland Magistrates Court on Monday.