In 2006, Therese took Peta to a motel in Toowoomba, under the guise of having a mother-daughter weekend.
She then plied her daughter with alcohol, before inviting a man, known simply as “Thommo”, to their motel.
After Thommo arrived, Therese asked Peta to go to the bedroom.
But a few minutes later, Thommo came in.
He then proceeded to rape her.
Peta said she repeatedly asked Thommo to stop, but he hardly even acknowledged her.
The whole time the attack was taking place, Peta's mum was sitting just outside, smoking cigarettes, complicit in her daughter's rape.
After the attack, her mother - who met Thommo online - gave her a hug and told her everything would be okay. That's when Peta knew her mother was responsible for what had happened to her.
Peta said her mother may as well have "murdered" her on that day.
It took Peta 10 years to come to terms with what happened to her that weekend, and to tell others her story.
"I wasn't strong enough for it at that time. I didn't think people would believe me," she said.
Eventually, she summoned the courage to call her mum, who is now in prison, to confront her. She recorded that phone call, and in doing so, secured the strongest evidence of her mother's complicity in the crime.
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And all these years later, Therese still shows no remorse for her part in enabling the rape of her daughter.
"It was still, yeah, it was still rape, but you were 16. I wouldn't let him touch you under 16, no way," Therese told Peta in a phone conversation.
While Therese is now locked away, disturbingly Thommo is yet to be found by police, who believe he has many other victims.