The other day I was in the car with the two kids after having picked them up from day care. I was talking with Eli about how we wear out seat belts so we don't fly out of the car if we get in an accident. The next thing I hear from him is something about pee in your pants and fly out of the car. He took “accident” as a peeing your pants kind of accident. So I then had to convince him that there are different kinds of accidents.
I can just imagine him thinking that he would pee his pants and then be ejected from the car if he wasn't wearing his seat belt.