But the bear came back

"Knock, knock. Who's there? A bear! A furry, friendly persistent bear. And no matter how many times a solitary little boy informs him that he should go home, the bear keeps coming back--until, one day, he doesn't. Before long, the boy realizes how much he cares about the bear...and misses him. Is there any way he can get the bear to come back?"--Provided by publisher.