Mary was born Jan 9, 1922 in Albion, PA. She came from an artistic and musical family; her mother painted and her father played violin. The family farmed in California and later Farmington Maine where Mary and her brothers Arthur, Ken, Gordon, Ernest and Douglas befriended a bear, a skunk and squirrels. Her brothers and sister Edith preceded her in death.

From an early age Mary took piano, organ and voice lessons. She graduated from the New England Conservatory of Music with a major in voice and organ. While in Boston she met her husband Ambrose Nangeroni who she married in 1943. Together they raised a chamber orchestra of 8 musical children. They moved to Milton in the late '40s and remained together until Ambrose died in 1996.

Much of her life was dedicated to social justice and civil rights issues. Mary was a tireless volunteer committed to helping end racism, domestic violence, poverty and other inequalities. She helped form, and served a term as president of, the Milton Civil Rights Fellowship. She served as board president of the Metropolitan Council for Educational Opportunity (METCO) program, Boston's voluntary school desegregation program. She also volunteered at Freedom House. In the summer she brought carloads of kids from Dorchester and Roxbury to her house to swim in the pool. She also volunteered at Rosie's Place (a sanctuary for poor and homeless women) and DOVE, an organization dedicated to ending domestic violence. She was a founder of the Milton Meals on Wheels program dedicated to ending hunger for seniors. Mary also volunteered with Hospice and often gave caretakers a day off by sitting with those who were ill and dying. She also served as an organist and choir director for several churches. She was recognized for her exceptional volunteer work at Milton Hospital where she led weekly sing-alongs and did other volunteer work for more than 20 years. More recently she helped form Milton's branch of the No Place for Hate program.

In the mid 1970s Mary was recognized for her community work with a Certificate of Appreciation for services rendered to the Boston Branch of the NAACP Educational Committee. She was honored by the Milton Mattapan Clergy Association in 2001 for her role in fighting for equality in Milton. Calling her an "unsung hero if there ever was one", they presented her with their Candle of Peace for living a life of justice. In 2010 the Milton Interfaith Clergy Association recognized Mary for "offering her best to the community of Fuller Village by attending to the struggles and joys shared."

Known for her generosity, Mary had a reputation for creating delicious and artfully decorated bakery goods including wedding and birthday cakes, gingerbread houses, marzipan shaped into fruit, cookies and sweet breads. She was an amazing gardener with more than a green thumb, known for being able to resurrect any plant. She also loved to read. Perhaps one of her greatest pleasures was visiting and playing games like scrabble with her large and diverse family and friends who miss the kindness of her spirit and her wry humor.