The foster brother of murdered Queensland schoolgirl Tiahleigh Palmer has been refused bail.

Trent Thorburn has been charged with incest and perverting the course of justice.

Tiahleigh's foster father Richard Thorburn has been charged with the 12-year- old's murder.

Trent Thorburn has been charged with incest and perverting the course of justice. Photo / Supplied
Trent Thorburn has been charged with incest and perverting the course of justice. Photo / Supplied

He didn't appear at Beenleigh Magistrates Court on Wednesday as his matter was briefly mentioned.

Advertisement

His lawyer Adam Dwyer told the court he was seeking a psychiatric evaluation for his client before the next appearance, which was set for February 22.

Tiahleigh's New Zealand mother Cindy and several supporters wearing her daughter's favourite colour purple crammed into the gallery of the small courtroom.

Upon hearing the news Thorburn would undergo psychiatric evaluation, one supporter said "he's not crazy, he's just a f***wit".

Police excavate a section behind the foster home of Queensland schoolgirl Tiahleigh Palmer. Photo / AP
Police excavate a section behind the foster home of Queensland schoolgirl Tiahleigh Palmer. Photo / AP