How little mouse Webster, who thinks he hates older brother Arnold, gets through the week when Arnold is off visiting Grandma. Day by day Roche shifts gradually from emphasizing the fun Webster has with his mother, the double bunks, and a huge piece of pie all to himself. . . to noticing the quiet that begins to disturb him. The outcome is as commonplace as the situation, but it's gracefully done; and the warmly colored pictures of Webster--exiled to a corner while Arnold packs, or going wild later with Arnold's feather headband and skateboard--have some personality.