When you're trying to teach your toddler, in the midst of his Terrible Twos, that he can throw tantrums all he wants, including in the middle of a diaper change, but that he will do so without getting any attention from you, and obviously (Murphy's Law), said toddler takes a dump on his bedroom floor, which startles him so much he starts to wail in misery, of course you clean him up and comfort him and tell him it's okay, but deep inside, you are really rolling on the floor choking with laughter.