Misery makes company

So Amy flagrantly lied about eating vaseline (yes, my child loves to eat vaseline...). Lid was off, there was a long finger hole in the vaseline jar, but Amy couldn't remember if she'd been near the jar, which was too high for Michael to reach (although at the rate he's growing, he'll be a great alibi in a few months). Lying is one of the few offenses for which spanking is the consequence in our house. After a tearful confession (only obtained when momma sadly told her we'd have to do a spanking for lying), Amy was given a spanking (over clothing I will add). She weeped, hollered, and wailed. I held her and calmly waited for the storm to pass. Through tear stained eyes she suddenly spied Michael, who'd wondered in to investigate the cacophony.
"Mommy!" She sobbed. "Give Michael needs a spanking, too!"
"Why?" I asked. I wasn't aware of any recent offenses warranting such a consequence.
"I don't know," she wailed. "Just spank him!"
Luckily for Michael, his mommy doesn't have a sadistic tendency. Now to figure out how best to eliminate that personality trait in Amy...