Collins' activities during her husband's mayoralty included serving a chairwoman of March of Dimes and on the boards of Faulkner Hospital and Boston's Museum of Fine Arts.

Collins was born Mary Patricia Cunniff in June 1920 in the Roxbury neighborhood of Boston, Massachusetts.

Before her birth, Collins' parents had immigrated to the United States from County Galway, Ireland and settled in Roxbury.

During her husband's political campaigns, Collins involved herself in his debate preparations by asking him practice questions and assisting him in refining his answers.

[3] During her husband's hospitalization, Collins ran his campaign as a co-manager, working from their personal residence in the Jamaica Plain neighborhood of Boston.

[3] Collins served for a time as a chairwoman of March of Dimes a nonprofit organization which raised funds for polio treatment and research.

[3][4] Collins served on the boards of several institutions, including Faulkner Hospital and Boston's Museum of Fine Arts.