Clark: Where do you think you're going? Nobody's leaving. Nobody's walking out on this fun, old-fashioned family Christmas. No, no. We're all in this together. This is a full-blown, four-alarm holiday emergency here. We're gonna press on, and we're gonna have the hap, hap, happiest Christmas since Bing Crosby tap-danced with Danny fucking Kaye. And when Santa squeezes his fat white ass down that chimney tonight, he's gonna find the jolliest bunch of assholes this side of the nuthouse.
After the tree burns up from Uncle Lewis' stogie, he turns around revealing fire on his back. Right as he is turning, the shot cuts to Clark and back to Lewis. In this new shot, Lewis' hair is different (compare the wigs), indicating the person getting the fire on his back put out is a stunt person.