Hero dad, 32, smashes window to save trapped sons during Melbourne house fire

A hero dad who saved his children from a house fire is fighting for his life after a blaze ripped through a home in Melbourne's north-west overnight.

An oil heater is believed the be the source of a fire which left four members of a family-of-five with serious burns in Hillside.

Firefighters arrived at the scene about 9.25pm to find the home engulfed in flames.

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The family, including three children, were asleep when the fire broke out and escaped their burning house as neighbours rushed to the scene to help.

James, 32, and his son Zayne, seven, remain in hospital in a critical conditon after suffering third-degree burns.

James is now in intensive care with burns across his body and deep cuts to his arms, according to a fundraiser set up for the family.

Zayne is also in intensive care with burns to his face, hands, and feet, where he remains in a critical condition.

James' partner Rochelle, 30, and their older son Izaiah, nine, suffered third-degree burns but are in a stable condition.

Their youngest child Ava-Leigh was not injured.

The two brothers were left trapped in their bedroom and James helped his children escape the burning home by smashing a window and pulling them out to safety.

The home sustained significant heat and smoke damage during the fire.

"They've lost everything. We have to rebuild with them," Rochelle's sister Andrea told 9News.

"I just don't think [Rochelle] realises the magnitude of what's happened, and she probably won't until she comes back up the road and sees that they no longer have a house."

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The two adults were taken to The Alfred Hospital while the boys were taken to the Royal Children's Hospital.

It took 40 minutes for firefighters to control the blaze.

An online fundraiser for the family has already raised over $30,000.

James' sister Laressa Turetahi said the family have a "long and painful road to recovery".

"This young family has lost their home, their belongings, and their sense of safety all in a single night," Turetahi said.

Neighbours and friends have visited the home to drop off essential items like nappies for the family.

The fire is not being treated as suspicious and it is believed a heater in the boys' bedroom caused the blaze.

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