The Perfect Brother is the second part of the 21st episode of Arthur Season 1. It day viewed with Sue Ellen Moves In on February 10, 1997.
Summary
The Brain is spending the weekend with the Reads because his parents are going to an ice cream convention. Arthur thinks this will be like having a brother around, but the Brain is neat, finishes his homework early, and reads to D.W., making Arthur look bad. However, Arthur discovers that the Brain is not so neat when the Brain invites Arthur over.