THOUSAND OAKS, Calif. (AP) One of television's most beloved big brothers has died. Don Grady played Robbie Douglas on the long-running 1960s hit "My Three Sons." He as 68. His "My Three Sons" co-star Barry Livingston says Grady died Wednesday. Grady had been suffering from cancer and receiving hospice care at his home in Thousand Oaks, Calif. 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. In later decades he worked primarily as a musician and composer, and wrote the theme for "The Phil Donahue Show."