(LOS ANGELES) -- Don Grady, who played one of the sons on the 1960s sitcom My Three Sons, died Wednesday in Thousand Oaks, Calif., at the age of 68, according to The Hollywood Reporter. He had been battling cancer.
Grady was a Mouseketeer on the Mickey Mouse Club before filling the role of Robbie Douglas on My Three Sons from 1960 to 1971. The sitcom starred the late Fred MacMurray as a widowed father raising his three sons.
Grady was also a composer who wrote the theme for Phil Donahue's long-running daytime talk show.
Barry Livingston, who played Grady's brother Ernie on My Three Sons, reportedly wrote on his Facebook page, "He was an inspiration to me in so many ways and his impact on my life is indelible. I will miss him greatly."
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