The Courier Mail reported that the revelation of a pregnancy occurred over Facebook messenger, where Trent confessed to his cousin that he'd had sex with the 12-year-old. He had also mentioned the sex to his mother.
Police prosecutor Sergeant Elen French said that the Facebook messages had been provided to police by his cousin, and though he had been interviewed by police five times about it, he had denied the sexual relationship each time.
“This defendant betrayed her trust. He abused his position as big brother and took advantage of her," French said.
“A consequence of that is her young life has been taken.”
Thorburn’s wife Julene, 54, and their older son Joshua, 20, have also been charged with perjury and perverting the course of justice.
In the wake of Tiahleigh’s tragic passing, the Queensland Government has ordered a review into the foster care system and the issuing of blue cards.
Child Safety Commissioner Cheryl Vardon will conduct the review of the foster system, which will closely examine approvals and blue card services
"The blue card system as it stands now is not broken," Vardon told the ABC.
"We need to improve it, we need to look at categories, we need to look at a whole range of things."
However the LNP's spokeswoman for Child Protection, Ros Bates, told the ABC they want an independent and external review into the Department of Child Safety.
"We need to make sure that we are protecting our vulnerable children and this minister needs to stop hiding behind privacy, stop hiding behind reviews.
"Come out and assure Queenslanders that children in care, particularly those in foster care are safe. There are obvious breakdowns in the system," she said.
"We need to have external people, external eyes actually look at the system and examine it for the flaws that are currently occurring."