David Derr O'Sullivan  (Age 87)  
Died on Thursday February 27, 2020 in Bethesda, MD. Beloved husband of Vonda, devoted father of Mary Humphrey, Janet Martinez (Ed) and Diane DePietro (Vince), cherished grandfather of Tara Kaczmarek (Tyler), Amy DePietro and Kelly DePietro, and great-grandfather of Oliver Kaczmarek. Funeral services will be held on Saturday, March 14, 2020 at 1 p.m. at St. Luke's Episcopal Church, 6030 Grosvenor Lane, Bethesda, Maryland 20814. Memorial contributions may be made in his honor to St. Luke's Episcopal Church.