I remember something from my education classes about Piaget's stages of cognitive development. In one of them, children basically think of everything in terms of themselves. I think Ms. Boo is in that stage. Here is the transcript from one our recent conversations:

Boo: Mommy, where are we going?
Me: to the bank
Boo: Where is the bank?
Me: in Miamisburg
Boo: No! MY amisburg!