Rick Thorburn has begun his life sentence for the callous and calculated murder of his foster daughter Tiahleigh Palmer after admitting to her shocking 2015 death in the Brisbane Supreme Court.
Thorburn was supposed to protect and care for the 12-year-old Logan schoolgirl but he killed her in a cold and sinister plan to cover his son's crimes.
He and his family had taken full-time care of Tiahleigh in January 2015 but almost 10 month's later he would murder her, dump her body on the secluded banks of a Gold Coast river and leave it to decompose.
Three fishermen found it five days later, almost naked and partially submerged, and an investigation into her death commenced.
Eventually, it would lead to charges against Thorburn, his wife Julene and two sons Trent and Joshua.
As Thorburn was sentenced to life behind bars for Tiahleigh's murder the court heard he had killed her after learning Trent had sex with her and feared she was pregnant.
Once he had murdered her, he tried to hide her body along the banks of the Pimpama River and developed a lie for the family to stick to.
Thorburn said Tiahleigh had stayed in bed on the night she was murdered and the next morning he drove her to school and saw her greet a friend.
The ruse came undone when police bugged the Thorburn family home and for about a month eavesdropped on conversations they believed were private.
Rather than protect his family, Thorburn's actions resulted in his wife and two sons serving stints behind bars and him facing at least 20 years in a cell.
In sentencing Thorburn on Friday, Justice David Boddice described his actions as despicable.
"You murdered this defenceless child who relied on you for protection," he said.
"Your offending involves truly appalling conduct."
Tiahleigh's biological mother, Cindy, lamented that Thorburn killed a beautiful girl with her life ahead of her.
"Rick Thorburn took that away from me, from our family and most of all Tiahleigh," she said outside court.
No sentence would ever be enough, she said.
"Today marks the end of a long fight for justice for Tiahleigh."
Thorburn will first be eligible for parole in September 2036.
Australian Associated Press
