FBI

"I want to be an FBI agent when I grow up," Adam said.
"I'm sure you'll make a great one," I replied. Olivia, Adam's younger sister, had been dunking her Barbie in a bucket of water. She dumped the water out as we were talking and ran off.
"Hey, what happened to the water?" Adam said, standing over the empty five gallon bucket in the parking lot.
"You tell me, Mr. FBI agent," I said. "This is your first case. What do you see? Empty bucket . . . wet pavement."