Dennis E. Gallagher

Obituary of Dennis E. Gallagher
Dennis E. Gallagher, 75, beloved husband, father, grandfather and friend, passed away peacefully on August 6, 2025, at Memorial Sloan Kettering Cancer Center in New York City, surrounded by his loving family, after a courageous battle with pancreatic cancer.
Born on September 7, 1949, in Orange, New Jersey to the late John R. and Dolores (McCarthy) Gallagher. Dennis was a lifelong resident of Union, New Jersey, graduating from Union High School in 1967. A 1971 graduate of Seton Hall University, he earned a Bachelor of Science degree in Marketing before answering the call to serve his country by joining the Army National Guard.
Dennis embodied hard work and dedication. For many years, he served as a skilled Diesel Mechanic for the Township of Union Police and Fire Departments, keeping the vehicles running and the first responders safe. He also co-owned PD Morris Avenue Sunoco Gas Station in Union, where he built lifelong friendships and earned the respect of the community with his knowledge, honesty and care.
Outside of work, Dennis lived a full life, creating happy memories with his family and through his passion for classic cars, coin collecting and listening to oldies music. He enjoyed spending time at the Jersey Shore and traveling, especially on family vacations to Grand Cayman. Dennis was a loyal New York Yankees fan and enjoyed cheering them on throughout the years.
Dennis married Susan (McCann) on October 9, 1983, and together they built a meaningful life raising three beautiful daughters and living a life filled with love, laughter and strong family values. He was a devout Catholic, family man and loyal friend and was always ready to help anyone in need.
He is survived by his loving wife of nearly 42 years, Susan Gallagher; his cherished daughters Katelyn Gallagher, Kelly Schmidt (Matthew) and Brianne Longest (Michael); his treasured grandchildren Logan and Lila Schmidt; and many extended family members and dear friends, who will miss him greatly.
Dennis was preceded in death by his parents and leaves behind a legacy of kindness, generosity and unwavering devotion to those he loved.
Visitation to be held on Wednesday, August 13, 2025 from 4:00 p.m. to 8:00 p.m. at the Madison Memorial Home, 159 Main Street, Madison, New Jersey.
A Mass of Christian Burial will be celebrated on Thursday, August 14, 2025 at 10:00 a.m. at Our Lady of the Blessed Sacrament Roman Catholic Church, 28 Livingston Avenue, Roseland, New Jersey.
Entombment will follow at Gate of Heaven Mausoleum, East Hanover, New Jersey.
Dennis' family would like to express our sincere thanks, gratitude and appreciation to Dr. Eileen O'Reilly, Gastrointestinal Medical Oncologist, and her team, along with the MSKCC staff in both New York City and New Jersey for the exceptional care they provided to him.
In lieu of flowers, the family would greatly appreciate donations to Dr. Eileen O'Reilly's pancreatic cancer research fund. Donations in Dennis' memory can be made through this link: Thank you.