Sam is a big boy. He is poop-in-the-potty big. He is stay-dry-through-the-night big. He is get-himself-dressed big. (See above.)
We played the "big boy" card so often while trying to get him to do those things, that he now thinks he is make-his-own-bedtime big, drive-the-car big, run-for-President big.
Me: No, Samuel. You may not have that [permanent marker]. That's not for little boys.
Sam: I am a big boy.
Me: Not big enough.
Sam: But, I pooped in the restaurant potty.
How can I even start to explain this to him?