Franklin was born in the United States on 3 February 1913. She graduated from Wilson College in the District of Columbia and later married William Franklin. The couple were living in Norfolk, Virginia in 1940, when William was a hotel doorman, and Mary was a saleslady in the retail sector.

In the 1950s, Franklin moved to Centreville, Maryland, and lived in a large house near the wharf. At this time, she was a teacher, and her husband worked in diplomatic service. Throughout her life, she was an avid collector of books and enjoyed playing bridge and reading poetry. At the age of 80, she moved to a nursing home in Chestertown, Maryland, where she currently resides.