Nothing.
5-year-old: A baby. Woman: What kind of baby 5-year-old: A human one. Nailed it.
With a blue elephant gun. You hold his trunk until he turns blue, then you shoot him with the blue elephant gun Edit: My 5 year old nephew loves this joke.
Neighbor
sigh "You're a pile of ants wearing a bathrobe." bathrobe sags dejectedly