SYDNEY – A pram carrying twin two-year-old girls rolled into the path of an oncoming train in Sydney on Sunday, police said, in an accident that killed one of the children and the “heroic” father who dashed to their rescue.One of the little girls survived only “through good luck” after she landed between the rails when the pram fell off a platform at southern Sydney’s Carlton railway station, police said.She was “largely untouched” by the train that apparently passed above her on its way to central Sydney in the early afternoon, police said.The parents had taken a lift down to the station…