There's fun on swings and fun in sandboxes. Fun with friends and fun with Grandma. Eating fun and bubble-bath fun and not-going-to-sleep fun. Once the fun gets going, sometimes it's hard for little ones to stop. Follow a day in the life of a very busy little tot who knows when it's time to move on. After all, every good-bye is really a hello — to something just as much fun. And that's good to know.