Mary M. Sullivan, 88, of the Town of Niagara, NY, passed away peacefully on February 26, 2026, at Buffalo General Hospital. Born in Barnesboro, PA, she was the daughter of the late John and Anna (Ycoback) Stelbosky.

Mary grew up in Barnesboro, where she attended local schools and graduated from high school. On December 27, 1958, she married the love of her life, Arthur T. Sullivan, Sr., in Pennsylvania. In 1960, they settled in the Town of Niagara, where they raised their five beloved children and built a home filled with warmth, love and laughter. Mary and Arthur were longtime parishioners of St. Leo’s Church, and she was a dedicated member of the First Catholic Slovak Ladies Axillary.

Mary enjoyed trips to the casino, took delight in collecting beer cans from around the world, and cherished any opportunity to gather with her family. As the family’s matriarch, she devoted her life to those she loved most. Her boundless compassion shaped every generation, and she poured her deep, unwavering love into her children, grandchildren, and great‑grandchildren, who will miss her dearly.

Mary is survived by her children, Arthur (Rosemary) Sullivan, Jr., Theresa (Wayne) Gould, Linda Sullivan, Lori Sullivan and John (Deborah) Sullivan; her grandchildren, Arthur (Jennifer) Sullivan III, Russell (Amanda) Sullivan, Courtney Gould, Brittany (Jason) Horowitz, Lexis Sullivan and Angela Malik; her great-grandchildren, Arthur IV, Jackson, Daniel, Isabella, Olivia, Owen, Brody and Brooke, as well as many nieces and nephews.

In addition to her parents, she was predeceased by her beloved husband, Arthur, and her three siblings, Helen (late Joseph) Blahovec, Jean (John) Staruch and Charles Stelbosky, who sadly passed away during World War II while serving in the United States Army.

Visitation will be held on Monday, March 2 from 4 -7 PM at M.J. Colucci & Son Niagara Funeral Chapel, 2730 Military Road, Niagara Falls, NY 14304, where funeral services will begin on Tuesday, March 3 at 10:30 AM, followed by Mary’s Mass of Christian Burial at 11:00 AM in St. Leo’s Church, 2748 Military Road, Niagara Falls, NY 14304. Entombment in Gate of Heaven Cemetery, Lewiston, NY. Memorial donations may be made to St. Leo’s Church. Visit mjcoluccifuneralchapel.com for online condolences.