Mary Theresa "Tess" (Hartner) Coster, age 69, of Seattle (Gig Harbor) Washington, formerly of McKees Rocks and Franklin Park. Passed away on Monday, June 20, 2022. Wife of Andrew Coster; mother of Andrea Coster. Sister of William Jr. (Mary Mancini) and John Francis (Tricia Ring) Hartner. Mary "Tess" was preceded in death by, parents Amelia (Baker) and William Hartner Sr. Also survived by nieces, nephews and great-nieces and nephews. Mary with her mother Amelia managed Hartner's Restaurant EST 1946 to 2006. Tess's smile and laughter will be remembered by all who knew her. She loved life and everyone was her friend. AS PER HER WISHES, THERE WILL BE NO VIEWING. Family and friends are welcome to attend Mass of Christian Burial on Monday, July 25, 2022 at 10:30 AM in Archangel Gabriel Parish, St. Mary Help of Christian Church, 1011 Church Ave., McKees Rocks, PA 15136. Burial to follow in St. Mary's Cemetery. In lieu of flowers, contributions in her memory may be made to The University of Pittsburgh, Alzheimers Research Center, UPMC Montefiore, Suite 421, 200 Lothrop St., Pittsburgh, PA 15213 (www.adrc.pitt.edu). Arrangements by SCHEPNER - McDERMOTT FUNERAL HOME INC., Crafton 412-921-3661. www.schepnermcdermott.com