A 50-year-old man ran into a burning Oshawa, Ont., home twice in an attempt to save people stuck inside, then became trapped himself before dying along with three others, according to a neighbour who witnessed the act of heroism.
Laura Green was outside her home attending to a broken pipe when she heard people yelling and shuffling out into the street Monday.
She said Steven Macdonald was "a decent guy" and a good neighbour in an area where everyone tries to "look after each other."
Macdonald as well as Lindsey Bonchek, 36, and her daughter Madeline, 9, were killed in the fire that gutted the two-storey downtown home. Bonchek's son Jackson, 4, was pulled from the fire but later died.
Seven others, who were in the house at the time, survived.
Green said she watched as he sacrificed his own life in an attempt to save those still inside.
"It was ... you can't even wrap your mind around it," she said.
"When everything first happened, he was trying to staunch the fire, but it had gotten out of control way too quick. He ran back in to save his own daughter, who was seven months pregnant," Green told CBC Toronto from outside her home.
"Then when she was out, there was another woman crying, 'My baby, my baby.' He went back in to see if he could save her."
While his daughter is among the survivors, Green said Macdonald never came back out.
"Steve heroically ran back into the building twice. Once to save his daughter, and then again, to save another child," she said.
"Knowing that people died in that fire, and that you were essentially watching their last minutes, it's horrific to get your head around."
Separate GoFundMe accounts have been set up for the Macdonald family and the Bonchek family.
The owner of a convenience store down the street from the home said Madeline and her younger brother would come into his shop a few times a week, usually to pick up a few groceries for their mom or to buy some potato chips.
"She was so good and she was always smiling," John Peerzada said.
He said he spent much of Monday thinking about the children. He would often stand outside his store, watching them walk home to ensure they made the trip safely.
"I wish I could have saved her life," he said.
The Office of the Ontario Fire Marshal is trying to ascertain what may have caused the fire.
"Once we determine where the fire originated, then we can examine possible ignition sources," said Richard Derstroff, an OFM investigator.
"But it's going to take quite some time to excavate through all the debris."
A key element of the probe will be to try to determine if the house was up to code and equipped with working smoke alarms.
"Smoke alarms are a huge deal for us because we want to determine whether there was any lack of early warning," said Derstroff.