Think of a funny song from your past that always makes you laugh. Then sing it to one of your kids. Sing out loud. Sing out strong. Sing of good things, not bad... sing of happy, not sad...
woops, sorry, a tangent.
Anyway, a couple of my favorites to sing to my kids are "If you want my body and you think I'm sexy come on baby let me know" and "Don't you wish your girlfriend was hot like me."
Sing it to them. Either it will get a laugh or they will leave the room, and depending on the day, either of those could be a plus!