Tiahleigh Palmer's foster father Rick Thorburn, who has been charged with murder over the 12-year-old's death, has been taken to hospital after collapsing in the Beenleigh watch house on Tuesday afternoon.
Thorburn, 56, arrived at Logan police station in handcuffs just before 11:30am.
He was later moved to the Beenleigh watchhouse where he was charged with Tiahleigh's murder. The girl's body was found on the banks of the Pimpama River last November, almost a week after she vanished in November last year.
About 4:00pm he collapsed and was taken to the Princess Alexandra Hospital in a stable condition, a Queensland Police Service spokesman said.
Thorburn is due to appear in Beenleigh Magistrates Court on Wednesday.
Son faces multiple charges
Rick Thorburn's wife Julene Thorburn, 54, was also brought to the Logan police station on Tuesday morning.
She has not been charged and is cooperating with police.
The Thorburns' 19-year-old son has also been charged with a string of offences including perjury in relation to the investigation.
Their other son, a 20-year-old man, has also been taken into custody.
The arrests came shortly after police confirmed Rick Thorburn was the former owner of a 2009 blue-coloured Ford XR6 sedan seized by police last week in relation to the investigation.
Police said last week the car's current owner was not considered a suspect.
At a 4:00pm press conference, his fourth of the day, Detective Inspector Damien Hansen said the day's developments had been tough on Tiahleigh's biological mother.
Earlier on Tuesday, Detective Inspector Hansen said the investigation had moved quickly in the past 24 hours.
"Due to certain factors we've moved quicker than than we possibly would have wanted to," he said.
Car still under forensic examination
He said police had received no further information in relation to the car since it was seized.
"We've looked at every person who had involvement with Tiah in this investigation," Inspector Hansen said.
He declined to say what police, if anything, had found in the car.
"It's still being examined," he said.
He said detectives had also updated Tiahleigh's biological mother on the investigation.
"She's comfortable with our response at this stage," Inspector Hansen said.
"But I will take the opportunity to say that also with the family that there are certain times we can't pass on information, when the information is at a critical stage.
"It's possibly been one of the most difficult investigations I've been involved in."
