My husbands family has this condition where they can fall asleep anywhere and while doing anything. It actually can be dangerous. Long time ago my husband fell asleep at the wheel of a car and totaled it. Luckily he came out just fine with no injuries. I don’t think it is as bad as narcolepsy, but pretty close. Here is an example of his little brother falling asleep WHILE playing a game on the Xbox. Not after the car race was done, but during the action of racing. Notice the controller has fallen out of his hands.