Gary W. O'Sullivan

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Mangano Family Funeral Home, Inc. - Deer Park

Posted events

October 26, 2025

Oct

Visitation

2:00 p.m. - 7:00 p.m.

Deer Park - Mangano Family Funeral Home

1701 Deer Pk Ave, Deer Park, NY 11729

Oct

Service

11:15 a.m. - 12:00 p.m.

Saints Cyril & Methodius R.C. Church

125 Half Hollow Rd., Deer Park, NY 11729

Mangano Family Funeral Home, Inc. - Deer Park

Posted a video

October 26, 2025

Mangano Family Funeral Home, Inc. - Deer Park

Posted an obituary

October 26, 2025

Gary O'Sullivan 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... Read Gary O'Sullivan's Obituary