Efrem Zimbalist Jr. was born in New York, New York, the son of Jewish parents - the famed Russian-born violinist Efrem Zimbalist, Sr.[1] and Romanian-born operatic soprano Alma Gluck.
You got his roots wrong. Gluck for sure was a Jewish woman, its a very common Jewish Surname.
I always liked his first name very Biblical, and distinctive
RIP Efrem
Efrem Senior did indeed have his children baptized and raised in the Episcopal Church.