Mary Louise Blair Peterson, 91, of Clarendon, PA, passed away peacefully on Sunday evening, September 6, 2020. Born August 6, 1929, in Warren, PA, the daughter of Fred and Mabel Fisk Blair. She was a 1947 graduate of the Warren High School and was formerly employed as an operator with Bell Telephone. Her joy in life was being a loving wife, mother, grandmother and great-grandmother. She was a member of the Clarendon Trinity United Methodist Church in Clarendon, PA, and the Sheffield Hospitality Center. Mary is survived by her children, Linda Goerlich and husband Milton, Warren, PA, Suzanne Peterson and George Armstead, Derry, NH, Jon Peterson and wife Cathy, Clarendon, PA, Pete Peterson and wife Annie, Moravian Falls, NC, Mary Ann Clark and husband Roni, Mount Joy, PA, Rebecca Jolie, and husband Ric, Miami, FL, and Robert Peterson and partner Jim Ramadei, New York, NY; thirteen grandchildren; six great- grandchildren; and several nieces and nephews. In addition to her parents, Mary was preceded in death on December 21, 2017, by her husband, Richard L. Peterson, whom she married on September 25, 1948, a son, Mark Peterson, and her brothers, Donald and Lawrence Blair.