Tiahleigh Palmer: Police to excavate home of accused murderer, foster father Rick Thorburn.

Queensland police are due to excavate the rural property of the foster family Tiahleigh Palmer lived with when she was allegedly murdered 11 months ago.

The 12-year-old was living with the Thorburns at Chambers Flat, south of Brisbane, for months before she disappeared and her body was later found on the bank of the Pimpama River.

Foster father Rick Thorburn said he had dropped her off at school on October 30 last year, but police allege he killed her the night before.

Earth-moving equipment has been seen at the Thorburns’ home, but police will not comment on what exactly they are digging for.

Thorburn, 56, collapsed in the Beenleigh watch house soon after his arrest on Tuesday.

Police are investigating whether he ingested something, reportedly pills, before or after he was taken into custody.

He was put in an induced coma, and woke up on Thursday.

He is in a secure intensive care unit at the Princess Alexandra Hospital.

Thorburn’s 19-year-old son, Trent, has been charged with incest.

Prosecutors will allege he “had sex” with Tiahleigh a week before she died and expressed fears to a cousin he had gotten her pregnant, despite believing he had withdrawn before ejaculation.

Tiahleigh’s foster mother Julene, who police will allege knew of the incident, and foster brother Josh, 20, have been charged with perjury and attempting to pervert the course of justice.

The schoolgirl’s mother, Cindy Palmer, will speak to the media this afternoon for the first time since charges were laid against the Thorburns.

She is expected to publicly thank the police and her supporters at a press conference at Logan, about 1:00pm.

This post originally appeared on ABC News.