Jo McGuire is 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, all the while trying to help make them better. She and Sam are very strict on her children and why they always punish Lizzie and Matt when they get in trouble. 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.