Mary's father was a Methodist pastor, and the family moved around Florida. She attended Leon High School and was chosen valedictorian before moving to Gainesville in the middle of her senior year. She graduated from FSCW in Modern Languages. While teaching in Crescent City, she met Claude Poag; they were married for 29 years. Later they lived in Tallahassee, and she worked for DoE for 26 years. She remarried in 1997; her second husband survived her, as did numerous direct descendants.