Donations for a Victorian family who lost their two youngest children in a shed fire have neared $50,000 as their heartbroken parents hold out hope for their two surviving children.
The siblings were playing together in the rear shed of a Corio property near Geelong on Sunday morning when it caught alight.
Three-year-old Saige McGregor and 18-month-old Ashlynn McGregor died at the scene while their older brother and sister, aged four and six, were flown to the Royal Children's Hospital in a critical condition.
The children's father, Kane McGregor, on Tuesday said doctors postponed surgery for his surviving son.
His mother found him huddled over his two youngest siblings so they would not burn, Mr McGregor said.
"He stayed there until he died himself. They revived him," he told reporters.
"I couldn't be any prouder of him."
Mr McGregor suggested police were probing whether the children were playing with a click lighter before the fire ignited.
GoFundMe organiser Daina Leech said the surviving children faced a long road to recovery.
By Tuesday evening, Ms Leech had raised almost $49,000 for the family.
"The medical treatment these children will require if they pull through this will be life long," she wrote on the GoFundMe page.
On another GoFundMe page, organiser Anthony McGregor - understood to be the children's uncle - said the surviving siblings had burns to most of their bodies.
The children's father on Monday said it had been the worst 36 hours of his life.
"Absolutely broken hearted having to let go of my two youngest baby's (sic). (The) only thing keeping me together is holding onto and fighting for my other two," he wrote in an emotional social media post.
"You are both so strong and way to (sic) stubborn to give in so keep fighting the winning fight as youse have this far and I'll lift the world for youse."
The children's aunt and uncle Sarah Guardiano and Anthony McGregor remembered Saige and Ashlynn as boisterous, naughty and loving.
Ms Guardiano said the children's mother ran into the shed and pulled her two eldest children to safety, sustaining burns to her hands.
"She did the best she could to get them all out as quickly as she did," she told reporters.
Anthony McGregor said the children's mother was destroyed by the loss of her two youngest and was staying at the hospital bedside of her surviving children.
A couch inside the shed, used as a dog bed, caught alight while the children were playing.
Police are not treating the fire as suspicious as arson and explosive detectives continue to investigate its cause.
