The Big Bang Theory

I was working one on one with a 5th grade boy. We were discussing the big bang theory within earshot of many other students and staff. "Ya want to know about the big bang, ask my Dad!" he said. (His Dad is a bookish, nerdy Phd. with whom I chat REGULARLY.) He continued "when he farts, it's the big bang and it's NASTY" Oh great. How am I supposed to keep a straight face the next time I see Dad.