Sarah Ristevski has spoken out about her mother's death for the first time, revealing she asked her killer father at least once if he was responsible.
"I can't get it out of my head," the 24-year-old says in a trailer for the upcoming interview on 60 Minutes, set to air on Sunday.
New Zealander Karen Ristevski, 47, vanished from the family's Avondale Heights home in Melbourne on June 29, 2016. Her decomposed body was then discovered in bushland at Mount Macedon Regional Park eight months later.
Borce Ristevski, her husband of 27 years, initially denied any involvement and carried her casket at her funeral, reports news.com.au
But the 55-year-old then confessed to her manslaughter in March last year, just as he was due to go on trial.
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Ristevski was jailed for nine years over the killing. His sentence was then increased to 13 years with a non-parole period of 10 years in December, after he refused to reveal why or how he killed his wife.
But Sarah has continued to stand by him.
She wrote a glowing character reference for him following his conviction, describing him as a "loving", "caring" and " protective" father, who "would always be helping mum out".
"Surely you asked your dad, did you do this? You asked him that? Did you kill my mum?" Liz Hayes asks Sarah in the interview.
"Even after he was charged, do you ask him: Dad did you do this?" she adds. "I think people need to know."
Sarah, putting on a brave face, responds: "I asked him if he had anything to do with it".
'I want to know'
In a telephone conversation recorded by police on a listening device in 2016, Sarah could be heard questioning her father.
She wanted to know why he turned his phone off for two hours as he drove past Diggers Rest in the direction of Mount Macedon on the day her mother went missing.
"You know what I want to know?" she said.
"You're out of the house for two hours, your telephone is off for two hours. You were driving and you turned your telephone off. They pinged you on the Calder (Freeway). So you were driving?"
But Ristevski deflected the question, telling Sarah he was being stitched up by cops who had no other credible leads.
"That's what (police) are trying to plant out there, Sarah," he said.
"That doesn't make sense," she replied.
"Nothing makes sense," he said.
Last year, a criminal profiler wrote a letter to Victoria's Director of Public Prosecutions, claiming Sarah was a victim of "coercive control".
"Sarah, Karen's daughter, declined to write a victim impact statement, an impact statement about her mother being brutally killed by her father," Ms Richards wrote.
"Her voice about the impact of her mother's brutal killing is yet to be heard, despite the fact she was close to her mother. She is no doubt conflicted but this is also instructive. Instead she wrote a glowing reference for her father — a man who lied to her and everyone else.
"This makes little sense unless it is understood that she too may be under his spell, which talks to his ability to manipulate and control those around him. Coercive control impacts children as well."