Grady's stage credits include productions of Pippin, Godspell, and Damn Yankees.
He was best known for his role as Robbie Douglas on the TV series My Three Sons. His other television credits include The Mickey Mouse Club, Wagon Train, The Rifleman, Have Gun Will Travel, and Dick Powell's Zane Grey Theater.
Grady was also a noteworthy musician, composer, and producer.
He is survived by his wife Ginny, his children Joey and Tessa, his sister Marilou Reichel, and his mother Mary.