UPDATE: The man accused of Tiahleigh Palmer's murder will not appear in court today as he is in an induced coma in the PA Hospital.
Rick Thorburn's lawyer informed the court of his client's condition at this morning's committal hearing in Beenleigh.
The 56-year-old's matter has now been adjourned until December 21.
His son, Trent Thorburn, who is charged with perjury and incest in the murder case, is scheduled to appear in court at midday today.
Tiahleigh murdered to protect son: Police
UPDATE 6AM: Overnight police have charged Tiahleigh Palmer's foster mother, Julene Thorburn and her son 20-year-old son Josh with perjury and preventing the course of justice.
The pair were released on Bail and are due to face Beenleigh Magistrates Court on October 10.
Earlier, her 56-year-old foster father Rick Thorburn from Chambers Flat, was charged with the murder of the 12-year-old Marsden schoolgirl.
Police are alleging Tiahleigh was murdered after Thorburn discovered an alleged relationship with his 19-year-old son Trent.
Police have charged the 19-year-old son with perjury and incest.
The father and 19-year-old son are due to face court this morning.
Yesterday's charges come after police last week revealed they had seized a car of interest.
Tiahleigh's mother Cyndi Palmer took to social media at the weekend, revealing the car had previously belonged to the foster father, Rick Thorburn.
Tiahleigh's body was found in November last year on the banks of the Pimpama River.
Man charged with incest, perjury in Tia Palmer murder case
UPDATE 4PM: A 19-year-old taken into custody this morning in relation to the murder of Tiahleigh Palmer has been charged with attempting to pervert the course of justice, incest and two charges of perjury.
Trent Thornburn's arrest comes after his father Rick Thorburn, 56, was charged with murder earlier today.
Detective Inspector Damien Hansen said a 54-year-old woman and 20-year-old man were still assisting police.
He said the woman had not been charged and was cooperating with police.
"All three of them I expect to be key witnesses," he said.
Detective Inspector Damien Hansen said Tiahleigh's biological mother Cydni had asked to be left alone.
"This has affected her greatly," he said.
The 12-year-old Marsden schoolgirl's body was found on the banks of the Pimpama River in November last year.
Foster father charged with murder of Tiahleigh Palmer
UPDATE 2PM: Police have charged the foster father of Tiahleigh Palmer with her murder this afternoon.
Rick Thorburn from Chambers Flat was taken in for questioning this morning.
Police have refused him bail and he has been remanded in custody to appear in the Beenleigh Magistrates Court tomorrow.
The 56-year-old was taken into custody along with his wife, Julene, and two men aged 19 and 20.
All four are known to each other and are continuing to assist police with their enquiries.
South Eastern Regional Crime Coordinator Superintendent Kerry Johnson said detectives had been working for 11 months towards this outcome.
"A team of dedicated detectives and police officers from the Homicide Group and the Logan District have been working long and endless hours to locate those responsible for her death," Detective Superintendent Johnson said.
"Make no mistake, this is an investigation that is close to the hearts of all officers whose sole aim was to bring her alleged killer to justice.
"The QPS values its relationship with the media and recognises that a strong two-way partnership is vital in order to appeal for public's help in solving crime.
"We want to thank them and the public for their assistance in this matter.
I also want to particularly thank the Crime and Corruption Commission for their continuing support and assistance."
Tiahleigh Palmer was reported missing on October 30 last year.
Her body was located at Pimpama on November 5.
Police questioning Tiahleigh Palmer's foster parents
UPDATE: Tiahleigh Palmer's foster parents are among four people arrested by police in relation to the murder investigation of the Marsden schoolgirl.
Her foster father, 56, was seen arriving at Logan Police Station just before 11.30am, in handcuffs.
A short time ago a woman aged 54, as well as two other men aged 19 and 20 were taken into custody by police attached to Operation North Mizzen - a joint Homicide and Logan District investigation.
Police say all four people are known to each other and were found at various addresses in Logan.
They are currently assisting police with their enquiries.
Foster father's link to murder case
EARLIER: Police have revealed that the car at the center of the Tiahleigh Palmer murder investigation previously belonged to her foster father.
The blue Ford XR6 sedan was seized by detectives last week and is currently being examined by forensic officers.
Tiahleigh's foster father had earlier sold the vehicle, however Detective Inspector Mark White said the current owner is not a suspect but "several persons of interest had been identified".
The 12-year-old was last seen alive on October 30 2015 when she was dropped off at school.
Her remains were located on the banks of the Pimpama River, near Kerkin Road North at Pimpama on the evening of November 5, 2015.
Police have appealed for anyone who saw a car matching its description on Kerkin Road North near the Pimpama River last October to come forward.
A $250,000 reward and immunity for anyone other than the main offender remains on offer, if they can supply information that leads to prosecution.
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