Gary W. O'Sullivan

Gary W. O'Sullivan obituary, Deer Park, NY

Gary W. O'Sullivan

Gary O'Sullivan Obituary

Visit the Mangano Family Funeral Home, Inc. - Deer Park website to view the full obituary.

Gary W. O'Sullivan, born on August 15, 1945, in Queens, NY, passed away peacefully on October 27, 2025, in Deer Park, NY. He was a cherished husband, father, grandfather, brother, and friend to many.

His Type A personality, paired with his selfless nature and opinionated charm, often filled the room with laughter and joy. He had a remarkable ability to find humor in everyday moments, leaving those around him with fond memories of shared jokes and warm conversations. Raised in Seaford, Gary cultivated a love for classic cars, boats, and fishing. His passion for automobiles once led him to own a Maaco auto body shop, reflecting his deep appreciation for the art of car restoration. This devotion to his hobbies was a testament to his spirited and adventurous character.

In addition to his enthusiasm for life, Gary is remembered for his steadfast love and devotion to his family. He was married for 40 years to Joanne, who he loved deeply. Together, they nurtured a beautiful family that includes their daughters, Kimberly Acquista and her husband Joseph, and Karen Seifert and her husband Justin. Gary was also a proud grandfather to Emily, Ana, Mia, Nicholas, and Joseph, whose lives he filled with encouragement and laughter. Loving dog Dad to Kiley. He is survived by his loving wife Joanne, daughters Kimberly and Karen, grandchildren, and his brother Richard O'Sullivan. Gary was preceded in death by his parents, Timothy and Anita O'Sullivan, and his brother Edward.

Visitation will be held on Wednesday, October 29, 2025, from 2:00 PM to 7:00 PM at the Mangano Family Funeral Home in Deer Park, NY. A Mass will be celebrated in his honor on Thursday, October 30, 2025, at 11:15 AM at Saints Cyril & Methodius R.C. Church, also in Deer Park.

Gary W. O'Sullivan leaves behind a legacy of love, laughter, and unforgettable memories. His presence will be dearly missed, but his spirit will continue to shine in the hearts of those who knew him.

IN LIEU OF FLOWERS THE FAMILY ASKS THAT YOU PLEASE DONATE TO ALZHEIMER'S: 

https://events.alz.org/fundraisers/kimberlyacquista/gary-w--o--sullivan---a-celebration-of-life?utm_source=qr&utm_medium=print

To plant trees in memory, please visit the Sympathy Store.

Mangano Family Funeral Home, Inc. - Deer Park

1701 Deer Park Ave, Deer Park, NY 11729

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