Beloved for his soft and gentle personality, Robert Young worked almost all of his life after Hollywood, even starring in the TV shows "Marcus Welby, M.D." and "Father Knows Best" Although, I cannot recall a musical in which he sang, Young did appear in many Musical films. My favorites being Cairo with Jeanette MacDonald and Honolulu with Eleanor Powell.

Essential Films:

Stowaway
Honolulu
Lady Be Good
Cairo
The Canterville Ghost