When I was little, my dad used to chase my sister and I up the stairs. He would bang his hands on the stairs and stomp his feet. We knew he was coming and we would squeal until we got to the top of the stairs and he would barely miss us. He did it all the time. So much so, that now I always make Jeff walk up the stairs in front of me, or if I am walking in front I cover my bum so he can't get it.
Anyways, sure enough I've started doing this to Carson. And he plays the part. He starts to move SO fast, he screeches and laughs hysterically. He starts to fumble seeing as he's only about 3 months into this whole stair climbing thing and he's just trying to move so fast. It cracks Jeff and I up.