A five-year-old girl became the saviour of her family when she heroically saved her mother and infant brother after they figured in a tragic car accident in Canada last June.

Lexi Shymanski was on her way back from a vacation trip in Calgary, Alberta, bound for Prince George, British Columbia, when her mother Angela passed out while driving their car on June 8, a Metro News report said.

Their SUV crashed into a tree before sliding down a 12-metre embankment, knocking out Lexi's mother who broke her back and suffered internal injuries.

Lexi reportedly woke up to the cries of her then 10-week old baby brother, Peter, who was later diagnosed to have suffered from internal bleeding in his brain.

Authorities said Lexi managed to escape the vehicle and hike up the steep embankment barefoot, and then called for help from a passing motorist.

"It's crazy. I can only remember one or two times where she got out of her five-point harness previously. She somehow got out, adrenaline or whatever, and barefoot hiked up the embankment," Angela told Metro News.

"The guy who came to see us in the hospital, he said the medics and the firemen needed ropes to get up and down that embankment, and she did it barefoot. It was only because she came up and flagged people down that anybody would have stopped," she added, according to The Inquistr.

After the first responder was able to get Peter out of the crashed car, CBC News said Lexi was able to flag down a motorist who happened to be a paramedic. This saved the life of Lexi's mom, the paramedic said, since any other rescuer could have just tried to pull Angela out of the car which could have killed her because she had a broken back. The paramedic called for back-up professional rescuers who were able to safely extract Angela from the wreck and transport her to hospital.

"If they would have jostled me a little bit, I might have been completely paralysed. It's hard to know," Angela said, referring to the bone fragment that became lodged inside her spinal column about a half centimetre from her spinal cord.

"It took him (paramedic) five tries before he could get cell service to call 911," she added, according to The Citizen.

The family was eventually airlifted to a hospital in Edmonton, where Baby Peter was rushed into surgery for severe brain bleed, after being first taken by ambulance to a health care centre in Jasper.

The Citizen said Angela—who suffered small fractures in her neck and upper back, as well as internal injuries including broken ribs and liver damage—is now recuperating and able to hold her four-month old baby in a wheelchair.

Lexi still seemed to be suffering from nightmares even after recovering from a small scratch on the left side of her face and neck pain, which doctors said was a result of a soft tissue injury she got from the crash.

"But I'm hoping when things settle down, those will disappear. I carry major guilt over this whole thing," Angela said, according to The Citizen.