Actor Don Grady, best known for his role in the 1960s sitcom My Three Sons, has passed away at the age of 68. Grady had reportedly been battling cancer.

Grady, born Don Louis Agrati, began acting in the late 1950s. He was an original member of the Mouseketeers when The Mickey Mouse Club began airing in 1955. His most well-known role is as Robbie Douglas on My Three Sons, which aired from 1960-1971.

Following the end of My Three Sons, Grady pursued a career in music, where he made a name for himself writing the theme music to various movies and television shows, including The Phil Donahue Show. He also released two studio albums – Homegrown in 1973 and Boomer: JazRokPop in 2008.

You can see some of Grady’s work below, including a clip from My Three Sons, and the Donahue theme.

Don Grady is survived by his wife Ginny, whom he married in 1985, and their two children, Joey and Tessa.