To Laugh or Punish?

I know that all parents have these moments - when kids do things that they shouldn't do, but it is just so funny that it is hard to punish them when you are laughing:) We had one of those events the other night. One of our favorite nightly activities is listening to Ava jabber and talk to herself after we put her in bed. After listening to some talking, we heard something that sounded like velcro coming undone. We both looked at each other and wondered what was going on since there is nothing in her bed that has velcro. Then I realized that it sounded like a diaper. So John proceeded to go in her room and found Ava buck naked in bed, holding her diaper and telling Daddy "yucky". Obviously, we do not want to condone this type of action, but it was rather funny and we couldn't help but laugh...