THOUSAND OAKS, Calif. >> Don Grady, who was one of television’s most beloved big brothers as Robbie Douglas on the long-running 1960s hit “My Three Sons,” died Wednesday. He was 68.

His “My Three Sons” co-star Barry Livingston, who played youngest brother Ernie, confirmed Grady’s death to The Associated Press. Livingston said Grady had been suffering from cancer and receiving hospice care at his home in Thousand Oaks, Calif. But the exact cause and place of death were not immediately clear.

“It’s the oldest cliche in the world when TV brothers start referring to each other like biological brothers, but he was the oldest, and somebody I looked up to and learned from a great deal about life,” Livingston said.

Born in San Diego as Don Louis Agrati, Grady had a brief stint singing and dancing on “The Mickey Mouse Club” starting at age 13.

But he was best known by far as one of Fred MacMurray’s “My Three Sons” on the series that ran on ABC and later CBS from 1960 to 1972.