Zoe on her way back from the mailbox:  I can’t run.  I don’t have enough energy.

Me Slightly shocked because she always has energy: Should we go get a snack to give you some energy?

Zoe: No, that wont work to give me energy.

Me:  It wont’?  Do you need some coffee?

Zoe: No, that won’t give me energy either.  Coffee makes me old.