Her father was a voice teacher, so I guess Andriana Caselotti got her talent naturally. Fortunately the apple that didn't fall far from the tree in this case was a good one, not one like Snow White (for whom Caselotti provided the voice) ate in the movie.
Some occupations and talents tend to run in families. Some are re-developed every generation. And some are just stuck. You can search of the 1930 census at Ancestry.com and see what category your relative falls into.
