Not to mention, try to keep a kid upright in their seat.
I have seen kids as old a 10 fall asleep in the car within minutes of the car leaving the driveway.
Something about the motion of a car puts them to sleep.
I had a cousin that would fall asleep on the back of his dad's motorcycle. Somehow he stayed on.
Little brother fell asleep in the back window of our 4 door sedan.