Age 69, of Collier Twp., formerly of Brookline, passed away on Monday, June 28, 2021. Beloved husband of 43 years to Becky (Piccolo) Doerfler; loving father of David Craig (Martha) Doerfler; cherished Pappy of Anna and Bradley Doerfler; beloved son of the late William and Lillian Doerfler; loving brother of Jeff and Lori Doerfler. Mark was a proud US Marine. Family and friends welcome Thursday, 2-4 and 6-8 P.M. WILLIAM SLATER II FUNERAL SERVICE, (412-563-2800) 1650 Greentree Rd., Scott Twp., 15220 where a Blessing Service will be held Friday, 10:30 A.M. Burial to follow in Mt. Lebanon Cemetery. In lieu of flowers, memorials may be made to UPMC Children's Hospital Free Care Fund.