To That Middle One who was dancing in front of the television with both hands shoved into the back of his pants:

"Hey, Middle One, what’s your problem? Stop scratching your butt in my living room!"

To which That Middle One replies:

"It’s my ass, Mama."

Judith’s Parenting Tip for Mothers with Smart-Ass Children #328: Beware of  the synonyms… They get you every time.