Gil Robbins, a musician and actor who was a member of the 1960s folk group the Highwaymen, died Tuesday at his home in Mexico, said his son, actor-director Tim Robbins. He was 80 and had prostate cancer.

"He was very charming, open and funny," Tim Robbins told The Times on Saturday. "He had a real strong moral center; he spoke up for what he believed in."

In 1962, Gil Robbins joined the Highwaymen, best known for "Michael," their recording of "Michael, Row the Boat Ashore." He spent three years with the folk group, singing baritone, writing songs and playing the guitarron, a large six-string guitar, on five albums.

Before joining the Highwaymen, Robbins performed with the Cumberland Three, the Belafonte Singers and folk singer Tom Paxton.

"I remember being very proud, seeing him on stage," Tim Robbins told The Times in a 1992 interview. "I'd go to folk concerts, where his group would be playing social protest songs and I'd be amazed to see 1,000 people singing along with him."

Gilbert Lee Robbins was born April 3, 1931, in Spokane, Wash., and his family moved to Los Angeles before he was 1.

Robbins played percussion with the Long Beach Symphony Orchestra while in high school and won a scholarship to study music at UCLA, where he became the marching band's drum major. He also met his future wife, Mary Bledsoe, who played the flute.

Robbins enlisted in the Air Force in 1951 and became a drum major and conductor stationed in Selma, Ala.

In the late 1960s, Robbins was a manager of the Gaslight, a popular folk music club in Greenwich Village. He was a stage actor in New York, and his movie credits included "Bob Roberts" in 1992 and "Cradle Will Rock" in 1999.

"I wouldn't be an actor if it wasn't for him," Tim Robbins said.

In addition to his son and his wife of almost 59 years, Robbins is survived by three other children, Adele, David and Gabrielle; a brother, Tom; and four grandchildren.

keith.thursby@latimes.com