(Mommy and 3 year old son snuggled up in bed pretending to be baby birds in a nest...)
Mommy: kisses son
Son: "Mommy, we can't kiss. Birdies don't kiss"
Mommy: "Why not?"
Son: "Because birdies have beaks."
Mommy: "Instead of...?"
Son: "Birdies can't kiss because they have beaks and not tongues."
(Mommy: mental note...find out who has been teaching my son to kiss!)