Robert Carradine, the veteran actor best known for playing dorky underdog Lewis Skolnick in “Revenge of the Nerds” and the warmhearted father Sam McGuire on Disney Channel’s “Lizzie McGuire,” has died...

The actor Robert Carradine, famous for roles in Revenge of the Nerds and Lizzie McGuire — among more serious parts — has died.

Carradine died after a “valiant” bipolar disorder battle, his family member told Deadline in a statement.