Why I was a shitty babysitter

Why do I find this funny? I am one sick bastard.

That's, Like, All We Did in Bio Lab Last Year
Girl #1: Did you know babies have natural reflexes? Like, if you stick your finger in their hand, they'll grab it, and if you try to pull it away, they'll hold on to it for like a minute.

Girl #2: Did you know if you punch a baby in the face, it'll cry?