Brenda Sue was Almanzo Wilder's ex-girlfriend.
They knew each other from back in school. They never really got along and had only one thing in common and that was music. They meet again after Almanzo and Laura marry. She is a singer, and has written one song called "My Only Love". She was rivals with Laura, since Laura is jealous of her when she sees her around Almanzo, thinking they have a affair. In a heat of Jealousy and anger, Laura attacked her outside of Nellie's Restaurant dirtying her dress with black ink. Despite the incident, Brenda Sue remained in Walnut Grove for a bit longer. On day while driving into town, she caught sight of Laura again apparently attempting to make amends by greeting her by waving at her. Brenda, probably frightened by Laura abruptly turned her carriage around and quickly drove out of town with all speed. (Episode 707: Divorce, Walnut Grove Style)