Two men, a man and his son are riding in a car that goes out of control careens into a ditch. Both the man and his son are unconscious when the ambulance arrives. Both men are taken to the nearest hospital. The older man, still unconscious is left in the emergency room and the the younger man also still unconscious is taken to the operating room because his injuries are more serious.
The surgeon walks into the room and says "I can't operate on this man because he is my son".
How could this be?
The Answer is now here.