Avery's first joke?

I was blow-drying his hair last night after bath-

A: Daddy, I want to push the button on the hair-dryer.
Me: Okay.
A: What happens if I push it up?
Me: It's on "low"
A: And what happens if I push it down?  (mind you, he knows the answers to these questions)
Me: It's on "hi"
A: Well, then, what if I push it down then up?
Me: "hi, low"
A: hahahahah.  "Hi-low", nice to meet you Daddy!