Robert Carradine, known for his roles in The Long Riders, Revenge of the Nerds and the television series Lizzie McGuire, has died at the age of 71, his management company told CNN.

His family said in a statement to Deadline that they were deeply saddened by his death, describing him as a father, grandfather, uncle and brother.

The family said Carradine had fought a nearly two-decade battle with bipolar disorder and hoped his journey would help reduce the stigma around mental illness.

His brother, Keith Carradine, said the family wanted people to know about his illness and that there was no shame in it.

Born on March 24, 1954, Carradine was the youngest son of the late actor John Carradine and the brother of actors David Carradine and Keith Carradine, as well as Christopher Carradine.

Carradine made his film debut in The Cowboys before building a long career in film and television.

He gained widespread recognition for playing Lewis Skolnick in “Revenge of the Nerds,” which led to sequels.

Two decades later, he reached a new generation of viewers as Sam McGuire in “Lizzie McGuire.”

Co-star Hilary Duff paid tribute on social media, expressing sadness at his death.

Another co-star, Jake Thomas, described him as funny, pragmatic and eccentric.

Carradine’s daughter, Ever Carradine, also shared a tribute, writing that her father was loving and supportive.