you know, I have a friend who works in the crime lab at the police station

Me: "Did you brush your teeth?"
Superman: "Uh-huh!"
Me: "Are you sure?"
Superman: "Yep!"
Me: "So if you didn't do a good job and you get some cavities, then Doug can give you a shot in your mouth and then drill a hole in your tooth. Maybe do you want to go try again, just to make sure?"
. . . pause . . .
Superman: "Yeah, I think so."