The Lizzie McGuire family is paying tribute to one of their own: Robert Carradine. The actor, best known for playing Lizzie's dad Sam McGuire in the hit Disney Channel sitcom, died at age 71 following a battle with bipolar disorder, his family said in a statement on Monday, February 23. "It is with profound sadness that we must share that our beloved father, grandfather, uncle, and brother Robert Carradine has passed away," Carradine's family told Deadline. "In a world that can feel so dark, Bobby was always a beacon [of] light to everyone around him.