Jessica Cowley told The Daily Telegraph her black Labrador retriever, Jet, broke free from her and shoved the stroller with young Jacob Cowley out of the way of the car.
"She is a strong dog and she pulled out of my hand and actually pushed the pram out of the way," Cowley said.
The newspaper said it appeared the car that hit Crowley had been struck by another car and pushed into her path as she was crossing the entrance to a parking lot near her Lancashire home.
Even though Crowley was hit by the car, she praised her canine companion for making the right move.
"Even while I was lying face down on the ground, I was happy to know Jacob was safe," she said.
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