The infant took it for a joyride while his mother slept and then crashed into a pick-up truck.
The boy was able to drive for about a quarter of a mile in Garsnas, Sweden.
During his ride, he successfully made three right turns before crashing into the truck.
The first that the mother heard of the incident was when a shopkeeper knocked on her front door, bringing home her son.
Speaking to Ystads Allehanda newspaper, the mother said: "When she explained that my son had been out driving the car I thought it was a terrible joke at first. I couldn't believe it was true.
"I have no idea how he managed, he's never driven a car before.
"I had the car keys in my jacket pocket and it was hanging so high that I thought he couldn't reach it. But he did. Don't ask me how, I was asleep."
Local police officers are reportedly not pressing charges and are simply pleased that no-one was injured.
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