THE 19-year-old teenage boy accused of murdering a mother and her two young children erupted into a bizarre rant while facing a Perth magistrate.

Michelle Petersen, 48, and her son Rua, 8, were found dead inside the Ellenbrook home, while her daughter Bella, 15, was found critically injured in the backyard but died on the way to hospital on Sunday.

Police said the crime scene was "complex" and "horrific", and it could take days for it to be processed.

Flanked by two security guards, Teancum Vernon Petersen-Crofts appeared in person at Midland Magistrates Court on Monday to face three murder charges.

He looked around the public gallery before sitting down and accusing another person of carrying out the attack.

"A criminal wanted to take me out bush - he did it and he came back for my family," Petersen-Crofts said.

Teancum Vernon Petersen-Crofts is accused of killing a mother and her two children. 
Picture: Facebook
Teancum Vernon Petersen-Crofts is accused of killing a mother and her two children. Picture: Facebook

The magistrate told him he didn't need to say anything, but he replied: "I have to 'cos mamma is with me".

After the magistrate said Petersen-Crofts would be sent to a psychiatric facility as there were concerns for his mental health, Petersen-Crofts said: "I was painting a picture of Jesus and stayed there for two months".

"He punched me in the head so hard. I left because I had to. I was that scared he was going to kill me.

"Mamma told me to save myself".

Petesen-Crofts then told a security guard standing by his side that he looked "like a serial killer."

He was remanded to the secure Frankland Centre unit at Graylands Hospital and will face Stirling Gardens Magistrates Court next week.

Police have confirmed he lived at the Ellenbrook home and it is believed he is related to the victims.

Teancum Vernon Petersen-Crofts, 19, faced the Midland Magistrate’s Court. Picture: Facebook
Teancum Vernon Petersen-Crofts, 19, faced the Midland Magistrate’s Court. Picture: Facebook

'CHILLS RAN THROUGH ME AND THE TEARS CAME'

A friend of the mother and her two kids who were murdered in their Perth home has revealed the harrowing moment she found out about the triple murder, and the family's tragic past.

Toni Ata, known as "aunty", took to social media to express her sorrow following the "horrific" killing of mother-of-five Michelle Petersen, 48, her daughter Bella, 15, and her son Rua, 8.

"I just found out the most devastating news that my friend and her two babies were killed last night … And I'm so, so devastated," Ms Ata said through tears during her live video.

She had already heard about the Ellenbrook murders, but a message from one of Ms Petersen's surviving daughters asking for a phone number confirmed her worst fears.

"I sent it back with a message saying 'hey gorgeous, here's the number, hope you're well'," Ms Ata said.

"To which she replied: 'Not really Aunty. Mum & Rua & Bella were killed this morning.'"

Ms Ata said she was shocked to the core and immediately started grieving.

"Chills ran through me and the tears came and came and came and came," she said.

"I sit here grieving for the whole family … it's just terrible … such a tragedy."

Mother Michelle Petersen who was killed. Picture: Facebook
Mother Michelle Petersen who was killed. Picture: Facebook

 

Bella Petersen, 15, who was killed. Picture: Supplied
Bella Petersen, 15, who was killed. Picture: Supplied

She said Ms Petersen had a troubled life, but was doing "so awesome" last time she saw her.

"Michelle had such a hard life," Ms Ata said.

"She lost two babies years ago when they were babies too: sudden infant death syndrome. "And she was an alcoholic for a really long time.

"I always thought if I lost two babies, I'd be an alcoholic too. Last time I saw her she had been sober for ages."

Ms Ata said Ms Petersen's son Rua was the light of her life.

The accused, Teancum Vernon Petersen-Crofts, is Ms Petersen's son, according to Ms Ata.

The deaths come just two months after Peter Miles, 61, his 58-year-old wife Cynda, their daughter Katrina, 35, and her four children - daughter Taye, 13, and sons Rylan, 12, Arye, 10, and Kadyn, eight - were found dead at their farm at Osmington, near Margaret River.

Ms Petersen’s son Rua, 8, was killed along with his mother and sister. Picture: Facebook
Ms Petersen’s son Rua, 8, was killed along with his mother and sister. Picture: Facebook
According to a family friend, Rua was the light of Ms Petersen’s life. Picture: Facebook
According to a family friend, Rua was the light of Ms Petersen’s life. Picture: Facebook


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