A car thief reported his own crime after discovering the vehicle had a seven-week-old baby boy in the back.
Police said a blue Subaru Impreza car was parked on Moor Road in Orrell, Wigan, at about 19:35 GMT on Tuesday.
Baby Leo's father Tom Moulsdale, 24, briefly left the car to enquire about some work at a house. The thief got into the running vehicle and drove off.
Police took an anonymous call 15 minutes later about a baby being left in a car three miles away in Billinge.
The abandoned vehicle was recovered and Leo was found unharmed.