Dad picked Sage up from school today. He reported this exchange:
Sage: "What's that?"
Granddad: "Oh, that's just some bird poop."
Sage: "Why is there bird poop on your car?"
Granddad: "Well, I probably parked under a tree, and then a bird that was in the tree pooped and it landed on my car."
Sage: "You shouldn't park under trees."