Uh-oh. It looks as if Rotten Ralph, Sarah's rapscallion cat, has gotten himself a rival in "very sweet cat" Percy. And he reacts just the way you'd expect: with a barrage of snowballs and a hole in Percy's Christmas stocking; by tying Percy to the model-train tracks, and pulling the ladder from under his feet when he's hanging a star on the Christmas tree. "He ate the milk and cookies Percy had left out for Santa Claus." And he puts "Ralph" on all Percy's presents. How much he's hurting we know when he finds Percy in his old place in Sarah's bed: "Sarah loves him more than she does me." But just as he's discovering that all the namby-pamby presents are Percy's, a little girl comes to the door: Percy's owner, come to take him home. With no more presents under the tree, however, Rotten Ralph still feels rotten--until ("Now it's time for us to exchange gifts") Sarah gives Ralph a new red bicycle, and he gives her a picture of himself, as Santa. We fade out on the two snuggled in an armchair: "You weren't jealous of the other cat, were you?" (Ralph, silently: "Nobody can take my place.") Rubel's antic, naive illustrations keep this open display of sibling rivalry at a delectable, cathartic remove--while the conjunction with Christmas ("Bad cats don't get Christmas presents") doubles the stakes.