I actually am a pretty big fan of those eps and I can tell you with relative certainty that that line is not in them. It doesn't sound familiar to me at all, but I'm wondering if it's a line from another popular tv show or movie. I have no idea which one or if that's even the case, but that would be my first guess.
~Anna
EDIT: Kathy posted at the same time as me, and I agree that the look on Lois's face would be priceless!
