Tiahleigh Palmer was last seen alive on October 30, 2015 when her foster father Rick Thorburn dropped her off near Marsden State High School in Logan, south of Brisbane.
On Tuesday afternoon, Thorburn was charged with Tiahleigh's murder. He was due to appear in court on Wednesday after being charged with murder and interfering with her corpse, but the 56-year-old was placed in an induced coma after collapsing in a Beenleigh watch house on Tuesday afternoon.
Here's what we know so far.
Six days after she was last seen alive, a fisherman found the 12-year-old’s naked body on the banks of the Pimpama River in south east Queensland. Her school shoe was also discovered in the same area on November 29.
In February police offered a $250,000 reward for information that would lead to arrest.
In March, an appeal for public information was made by Tiahleigh's biological mother Cyndi, who had been preparing for a custody hearing to get her daughter back when Tiahleigh went missing.
That month police forensically examined an empty housing commission home near Tiahleigh's school in Logan and urged anyone who might have seen her near the property to come forward.
On September 13, a blue Ford XR6 was seized by police who said the car had been recently sold and the current owner was not a suspect.
Cindy Palmer took to social media and outed Rick Thorburn as the former owner of the car.
On Tuesday, Thorburn, who was a pallbearer at Tiahleigh's funeral, was charged with her murder.
His 54-year-old wife Julene and 20-year-old son Josh were charged with attempting to pervert the course of justice and perjury.
Tiahleigh's foster brother Trent Thorburn was also taken into police custody and charged with incest, attempting to pervert the court of justice and two counts of perjury.
The 19-year-old is accused of having an illegal sexual relationship with the 12-year-old during the 10 months she was in the family’s care.
Police will allege Rick Thorburn murdered Tiahleigh to protect his son after discovering the relationship, the Courier-Mail has reported.
Trent Thorburn allegedly told a cousin in a Facebook message that he had sex with Tiahleigh and thought she might be pregnant, a Brisbane court heard on Wednesday.
Magistrate Pamela Dowse said the 19-year-old was not a suitable candidate for bail at this time.
The police prosecutor alleged Tiahleigh told her foster mother Julene that Trent Thorburn had sex with her.
He was asked on five separate occasions if he was involved in her death or had sexual relations with the child, and he denied it, the prosecution said.
“Whilst Mr Thorburn is at risk of a prison sentence in relation to this charge, it is certainly not a given,” his solicitor John Ide said.
Two weeks ago Trent Thorburn posted an Instagram selfie with a caption: "Life has it's [sic] ups and downs, goods and bads! Everyone has to go through challenges in life that they wish they never had to! But when you have food in your mouth, cloths [sic] on your back, a roof over your head, family and friends, life is good. Never forget to love and spread the love, smile and celibate [sic] life! Life is good, life is what you make it!"
Rick Thorburn's lawyer Kelly Thompson told a court hearing his client had been put into an induced coma and there was no indication of when he would be conscious again. The case was adjourned until December 21.
Gina Rushton is a breaking news reporter for BuzzFeed News and is based in Sydney.
Contact Gina Rushton at firstname.lastname@example.org.
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