Donations may be made in Mary Ann's memory to:    www.bloodcancerunited.org/office/long-island-ny 

Mary Ann O’Brien, 79, entered into eternal rest on January 11, 2026 after a long battle with cancer.  She was born on October 3, 1946, and raised in Mineola, New York, where her Catholic faith, family values, and strong sense of service took root and guided her throughout her life.

A devoted Catholic, Mary Ann lived her life grounded in faith, prayer, and love for others. She was the beloved wife of Thomas O’Brien and a loving mother to four children: Denise (husband John), Thomas O’Brien (wife Laura), Kenneth (wife Jennifer), and Michael (wife Stefanie). She was a proud grandmother to her eleven cherished grandchildren: JT, Ryan, James, Ashley, Colette, Drew, Kylie, Rhys, Charles, Christopher, and Joseph, each of whom was a true blessing in her life.

She is also survived by her siblings, Marguerite, Kathleen, and George. She was predeceased by her parents George and Elizabeth Wallace.

Mary Ann dedicated many years of her life as a postal worker, serving her community with reliability and kindness. Her greatest vocation, however, was her family. She found joy in caring for those she loved, gardening and creating a warm, welcoming home. She was known for her thoughtfulness, especially in the way she gave gifts—always carefully chosen, personal, and given with love. Her home in Florida was a place of peace and renewal, where she enjoyed being with her husband and friends.

Mary Ann’s life reflected her deep trust in God and her belief in the promise of eternal life. She will be remembered for her gentle spirit, generous heart, and unwavering faith. Though she will be deeply missed, her family takes comfort in knowing she now rests in the loving arms of the Lord.