Josephine Lynn "Jo" McGuire was Lizzie and Matt's mother. She cared deeply about Lizzie but was still trying to figure out how to raise a teenager. As a result, she sometimes tended to "mess up" situations in Lizzie's life while trying to help make them better. At the end of each episode, Jo and Lizzie tend to come to an understanding and portray the unfaltering love of a mother-daughter relationship. Her birthday is July 28.