A bunch of kids are clustering around a computer and I tell them they have to leave because only two people can be on at a time.
So immediately they move to another computer, and look on with the two guys there.
Me: What did I just tell you?
One kid: But he's my brother!
Me: It doesn't matter WHO he is, you can't have more than two at the computer.
Kid: But there's only two of us here!
Me: Um, hi. There are three of you.
Kid: Oh, fine. (To other kids) Let's just go read a book.