Tuesday afternoon started out as the average routine for an Ottawa-area mother and her two small children, but that's not how it ended.

Melissa Davey was driving to her home in Greely from the grocery store on Aug. 1, her kids loaded in their car seats behind her, when she caught a glimpse of her three-year-old boy in the rearview mirror.

Howie's face was grey, the seatbelt beside him fully extended and wrapped like a noose around his neck.

He'd taken the middle seatbelt and twisted it and twisted it the way you'd tie a tourniquet around something. - Christopher Wallace, father

"He'd taken the middle seatbelt and twisted it the way you'd tie a tourniquet around something," said Christopher Wallace, his father.

"He had wound it really tight and just enough to pull it over his head."

Panicked, she pulled the car over and dug through the glove compartment looking for scissors.

When she found none, she waved for help while trying to loosen the belt from around Howie's neck.

No one stopped and the seatbelt wouldn't move.

"Not even an inch," said Wallace.

A man in uniform

As Davey tried to give her son enough slack to breathe, she realized she wouldn't be able to call for help and keep the seatbelt from reverting to its deathly grip at the same time.

"Suddenly this car pulled up and this young man in [a military uniform] jumped out," recounted Wallace on Saturday. "He said 'I got a knife, I can cut the seatbelt.'"

Within seconds, the toddler was free and screaming in his mother's arms.

Cpl. Shane Chafe cut the seatbelt with his knife, saying it was what 'anyone would do if they were able to.' (Facebook)

Cpl. Shane Chafe said he was just at the right place at the right time.

"I was just driving home from work and I saw a lady on the side of the road," he said.

"When I went up to her vehicle I could see that her kid was trying to cough and he had the seatbelt wrapped around his neck."

The odds of someone stopping who happened to be carrying a knife were slim, Wallace said, calling Chafe the "ideal person" to show up in that desperate moment.

"If he hadn't have come along, Howie may not be here," she said.

'Imagine losing him to something like this'

But Chafe was an unknown rescuer, as Davey didn't ask his name before she drove away.

When the family reunited at home, they posted across social media looking for the man who had saved their son.

That same day, Chafe's girlfriend saw the post and connected with them.

"He deserves a medal," said Wallace, explaining that the family wrote to his military base recounting what happened, and the "miracle" of Howie's life.

Their little boy has spent most of his life in and out of SickKids hospital in Toronto. Wallace said he barely survived to see his first birthday.

"That magnified how powerful this was," he said. "Imagine losing him to something like this, at the side of the road, to a loose seatbelt."

After reflecting on the experience, Chafe said he was just doing the right thing.

"I just wanted to make sure he was OK," he said. "I figure it's just something that anyone would have done if they were able to."