Rick Thorburn gave his son a cover-up story for Tiahleigh Palmer’s killing

SECRET police recordings have revealed sick cover-up methods the Thorburn family used to cover up Tiahleigh’s brutal murder.

THE killing of 12-year-old Tiahleigh Palmer — who was taken in to care by a seemingly normal foster family before she was smothered to death — is becoming increasingly disturbing with each new detail.

Last night, 60 Minutesunearthed secret police recordings, disturbing confessions and chilling Facebook messages which show just how far the Thorburns went to cover up the sickening crime.

Cops bugged the Thorburns’ house shortly after Tiahleigh’s body was found washed up on the banks of the Pimpama River — and what they uncovered was shocking.

Sick foster parents Rick and Julene Thorburn can be heard scheming and telling their sons Trent and Josh how to keep up the lie that Tiahleigh was dropped at school — when she was in fact already dead.

Days before her death, foster brother Trent Thorburn, 18, had become concerned he had impregnated Tiahleigh.

The 12-year-old had also told a friend that Trent was having sex with her when Julene left the house.

Trent also confessed his wrongful relationship to a cousin, who then told his mother Julene.

Within 48 hours she would be dead.

Tiahleigh Palmer was murdered by her foster father Rick Thorburn. Picture: Channel 9

“We have to stick to the same story about her going to school the next day and whatever,” Julene can be heard saying in the police recording.

Rick even coaches Trent on what to say if he is questioned about the rape of his 12-year-old foster sister.

“She came into your room, you remember waking up, you were still drunk, you were still ... whatever,” Rick Thorburn said.

However, the family don’t seem entirely united behind their killer dad’s cover-up plot — as Julene and eldest son Josh discuss telling the truth.

“If we have to come clean that’s just between you and I,” Julene said.

“Dad made the decision to go down that path unfortunately.”

60 Minutes also revealed a disturbing Facebook message which led to the unravelling of the family’s cover up.

In the message, which was leaked to police from Trent, the teenager writes that he had sex with his foster sister Tiahleigh, and appears to be concerned that she may be pregnant.

The Thorburn family were found to have lied about their role in the plan. Picture: Channel 9

Rick, who was sentenced to life imprisonment on Friday for the sickening murder, was even being watched by his wife as he backed his blue Ford Falcon into a shed shortly after the killing in September 2015.

According to the statement to police in 2016, Julene couldn’t see what her husband was doing in the shed for half an hour at around 8pm that night because her view was blocked by trees — but she knew her dead foster daughter was being loaded into the boot.

Details of the statement, obtained by ABC, also reveal how Rick ordered his teenage sons Joshua and Trent Thorburn to leave the house and go to places where they could be seen by other people as he worked to dispose the body.

“Don’t ask any questions … try to be normal — the less you know, the better,” Rick told the family the night he stuffed Tiahleigh’s body in his car, according to Julene’s statement.

When she and her sons came home the next day, he bluntly told them he had “taken care of it”.

Rick Thorburn. Picture: Jack Tran/ News Corp Australia

Trent’s Facebook message. Picture: Channel 9

Tiahleigh’s mother Cindy Palmer told 60 Minutes she ‘fell to the ground crying’ when she was told her daughter was dead. Picture: Channel 9

And, when she asked him what he meant by the statement, he was vague in his reply.

“Don’t ask any questions, you don’t need to know,” he told her. “I have taken care of it. We do things like we normally do.”

Tiahleigh had been taken in by the Thorburns after a childhood spent living with her drug-affected single mother Cyndi and spells in and out of care homes, the little girl had spent two happy years with Gympie foster mother, Julie Pemburton.

Alarm bells were set off in Ms Pemburton’s mind when Tiahleigh occasionally played truant from school and told her she “hated” her new home, although the exact nature of her misery wasn’t clear.

It all came to a head on September 27, 2015, when Instagram-obsessed Trent confessed his wrongful relationship to a cousin, who then told Julene.

After that, the 12-year-old schoolgirl’s days were numbered; within 48 hours she would be dead. Rick Thorburn would later tell police that he had dropped Tiahleigh off at school at 8.10am on Friday, October 30.

Fishermen found Tiahleigh’s badly decomposed body floating in the Gold Coast’s Pimpama River

Rick Thorburn continued the cover-up on Facebook.

That morning, Joshua Thorburn was told not to go into his foster sister’s room.

He walked past her door but did not look.

His father Rick had smothered Tiahleigh the night before to prevent any scandal about brother Trent’s sexual relationship with a child.

Josh would later lie to police, telling them he’d spoken to Tiahleigh in the morning as she’d been getting ready for school, before she ran away.

But it was his mother Julene who had orchestrated the cover-up, because she did not want to lose her “family and lifestyle”.

Julene and Rick held a family meeting with Trent and Josh, telling the boys “it’s all been taken care of”.

That evening on Facebook, Rick Thorburn advanced the lie, posting messages about the girl’s disappearance and garnering sympathy and help.

“If any of her friends are hiding her again, please do the right thing and let us know,” he wrote at 11pm on the Friday. “She needs to come home where she belongs.”

Six days later, three fishermen found Tiahleigh’s badly decomposed body floating in the Gold Coast’s Pimpama River, 30km south of where she was last seen.

Trent Thorburn was charged with incest, pervert the course of justice and perjury. Picture: Instagram.

Detectives charged Rick Thorburn with Tiahleigh’s murder and with interfering with a corpse.

They charged Julene and Josh Thorburn with perjury and attempting to pervert the course of justice.

Trent Thorburn was charged with incest, attempting to pervert the course of justice and two counts of perjury.

Trent and Rick Thorburn were denied bail, and the father collapsed and was taken to hospital for a suspected heart attack.

Last year, Trent Thorburn began a maximum four-year, minimum five-month sentence for incest and his other charges.

Joshua Thorburn received a three month sentence, and Julene a maximum 18 months.

Rick Thorburn will spend the rest of his life in jail after pleading guilty to murdering the 12-year-old. He will need to serve 20 years in prison before being eligible for parole on September 12, 2036.

— with Candace Sutton