Sean was yelling from downstairs... he apparently needed his butt wiped.
I headed down to find him sitting on the potty. He was complaining about how Max had sniffed his butt. He said that Max sniffed his butt because he smelled poop in his butt.
He was upset because Max sniffed his butt and Ethan's butt and Mommy's butt and Daddy's butt and Max sniffs everyones butt!
I explained that that is what dog's do.
Reasoning enough. He accepted the answer and we were done talking about doggy butt sniffers.