Scott and His Belly Button

Whenever he isn't busy doing something else like drawing on my walls or handing me live beetles, Scott walks around sucking his two middle fingers on one hand and poking his own belly button with his other hand. If I keep him in shirts that snap at the crotch or overalls, I can foil his attempts and keep him just poking his clothes all day. But if I succumb and put him in a regular shirt, he pokes his belly button raw. But today was a bit more ridiculous. I caught him trying to put objects INTO his bellybutton. I mean LARGE objects. Flashlights, toy trains, water bottles, etc. Scott's belly button is currently an outie because he's got that toddler-with-internal-organs-too-big-for-my-abdomen-so-I-have-a-
pot-belly look going on. His belly button currently sticks out more than mine did 9 months pregnant with either kid. So why would he try to put anything in it? There isn't even space for any lint, let alone household objects...