Sally, sister of Charlie Brown, is both beloved and the cause of endless frustration. She is constantly riddled with self-doubt, annxiety, introspection, and fear. When it comes to school, her anxiety "reflects much of the frustration and confusion kids experience."

She often worries about not having the answers, even if it is her first day of class: How can she show up to school and not know everything? She harbors a not-so-secret crush on Linus, her "Sweet Baboo," and often gets angry at him when she feels her affection has not been returned. It was also through Sally that Schulz tackled certain religious issues, particularly prayer in school.