The son of one of the victims of Dreamworld's ride disaster saw his mother's fatal fall when the Thunder River Rapids ride malfunctioned.
Sydney mother Cindy Low, 42, was at the theme park with her 10-year-old son Kieran, six-year-old daughter and her husband Mathew on Tuesday.
However, she made the tragic decision to separate from her daughter and husband and ride in another raft with her son and four strangers.
She died on the ride's wooden conveyor belt when her group's inflatable raft crashed into another raft, flipping and killing four of the six people inside.
Kieran saw the entire event and was being comforted by his father on Wednesday.
He was thrown from the raft alongside the 12-year-old daughter of another ride victim, Canberra mother Kate Goodchild, 32.
The fact both children survived is "a miracle", police said on Wednesday.
"A beautiful wife, mother and dear friend was killed today while enjoy[ing] what should have been a relaxing family holiday," one friend of Ms Low said in an online tribute.
It's not believed that the Low family knew the three Canberra holidaymakers who were also killed.
Ms Goodchild's two daughters were taken out of the park screaming and crying along with their father, who emerged from the ride covered in mud, witnesses said.
Ms Goodchild's brother Luke Dorsett, 35, and his partner Roozbeh Araghi, 38, were also killed.
It was the worst Australian theme park disaster since 1979, when seven people died in a fire on the Ghost Train at Luna Park in Sydney.
Ms Low was originally from Kawerau in New Zealand but settled in Sydney years ago, most recently on the lower north shore, with her children and husband, a business systems specialist for a hearing aid technology company.
She was on a holiday at the Gold Coast with her family and some friends. It is understood the group were all at Dreamworld on Tuesday.
Queensland Police Assistant Commissioner Brian Codd said the two children, aged 10 and 12, were thrown into the water but survived.
"In terms of how they escaped, maybe through the providence of God," he said.
"It seems from what I've seen [on CCTV] it was almost a miracle that anybody came out of that. If we're going to be thankful for anything, I'm thankful for that."
He said it was "absolutely traumatic for these children" and they were being looked after by their families.
He said CCTV showed that the raft was coming to the end of the ride and had been pulled up a wooden conveyor belt. A malfunction caused the raft to collide with another raft and flip backwards.
All six in the raft were wearing velcro lap belts.
Two adults were trapped under and two were thrown into the water.
Dozens of people witnessed the accident, including an English tourist who told Fairfax Media she saw a woman hanging by her leg from the raft. Others ran from the ride's entrance screaming and crying.
The raft has been removed from the park for forensic examination.
Engineering examinations will continue at Dreamworld on Wednesday and it is expected the ride will be closed for at least two or three days.
Note: Police initially said in a press conference on Wednesday that two girls, aged 10 and 13, were thrown into the water, but police have now clarified that should have been a boy, aged 10, and a girl, aged 12.
