No Fighting, No Biting!, by Else Holmellund Minarik, illustrated by Maurice Sendak, 1958, HarpersCollins.
This book is almost as enchanting as the Little Bear series. Probably because no matter how adorable the baby alligators look when created by Maurice Sendak, they just don't have the cuddliness of a bear cub. A side effect of this book is that my seven-year-old son will point to our two older cats when they are tussling and say, "No fighting, no biting!" I'd say he fully understands the story.