As we drove to day care today, I turned on Pink Floyd's Animals album and played the "Pigs on the Wing (Part 2)" track.

"Listen, guys; do you hear that noise? What is it?"

"It's pigs, Daddy!"

"Yep. This song has pig noises on it. Keep listening--they make pig sounds a few more times."

(Two minutes later)

"Daddy, I hear the pigs again."

"Yep, there they are, Drew."

"Daddy?"

"Yes, Drew?"

"Are the pigs the ones making the music?"