Did Pete go back to pick up Donald?
The story of The Rich Brother by Tobias Wolff contrasts two bothers, Pete, who is conventionally successful and Donald who is less practical and more spiritual. While Pete is in many ways happily married and well-adjusted, he is still spiritually insecure, feeling that Donald is judging him and that he is in some way failing a spiritual test. Nonetheless, when Donald is expelled from a religious commune, Pete drives down to pick up Donald, functioning as he has since their parents' death as Donald's caretaker.
Donald's character is illustrated in the way that he offers a lift to a rather dodgy character who is hitchhiking and then gives the hitchhiker the $100 that Pete just gave him, in theory as an investment in a (probably fictitious) gold mine. Pete is angry and kicks Donald out of the car. However, after driving a short distance, Pete feels guilty and turns around to pick up his brother. Although we know that Pete intends to pick up Donald, the story ends before he actually does so.