Knock Knock

K: Daddy?
Daddy: What?
K: Don't cry it's only a joke.
K: Knock knock
D: Who's there?
K: Orange
D: Orange who?
K: Banana
K: Knock knock
D: Who's there?
K: Apple
D: Apple who?
K: Don't cry it's only joke.

(Now repeat something similar for at least 15 minutes with maniacal preschool laughter after each round, and you have an idea of our evening...)