Queensland girl fights for life after fatal crash

A four-year-old girl is fighting for her life in hospital after a horrific crash on Queensland's Sunshine Coast that killed her mother, brother and sister.

Keisha Jackson, 30, and two of her children, Ryan Jackson-Cook, 10, and Joan Jackson, seven, died after the family's four-wheel-drive skidded off the Mooloolah Connection Road at Glenview, south of the Sunshine Coast, on Friday night and hit a tree.

Four-year-old Matilda Jackson was taken to the Royal Children's Hospital in Brisbane with serious injuries.

Her family has asked for privacy while she receives treatment.

Her brother Ethan, 11, the only other survivor, was discharged from the Nambour Hospital on Saturday.

Ms Jackson's friends have taken to social media to pay their respects.

"I wished this has (sic) never happened to you," friend Amanda Lando wrote on the mother-of-four's Facebook page.

"I hope I will see you in the next life in the spirit world and your kids as well.

"You will always be in my heart for ever."

Police are continuing to investigate the cause of the accident but officers on the scene initially indicated speed could have been a factor.