Sylvia was born to Hyman and Fannie Cranberg in New York City where she lived until 1948. She and her husband, Dr. Jack Troy, came to Indiana, living first in Whiting, then Munster, then Beverly Shores.

While raising her children in Munster, she became active in the League of Women Voters and then discovered the Indiana Dunes, which became her lifelong passion. She served as President of the Save the Dunes Council for 10 years and was instrumental in the creation of the Indiana Dunes National Lakeshore, which just recently received the designation of Indiana Dunes National Park.