Shirley Maxine Petersen, 82, passed away peacefully surrounded by her family on November 13, 2020 after a courageous battle against Acute Myeloid Leukemia. Shirley lived her life for her children, raising three on her own. Even though it was challenging, the kids never felt her burden. She still pulled off fishing trips, skating on Baker Lake, pizza burgers at The Big K, and the coolest duds from Russell’s. In July of 1980, the family experienced a mother’s greatest nightmare of losing Clint in a tragic accident. His absence was forever felt, and she will be buried next to him. Shirley was very caring and generous, looking for every QVC item to buy her children and granddaughters for Christmas. In April 2019, she was thrilled to welcome the newest member, her great grandson, Teddy. She redefined the title great grandma. Shirley was born on September 16, 1938 to Tom & Maude Tillman in Bozeman, MT, she was the 12th of 13 children, and the last one to join her family in Heaven. In her early years, Shirley worked for Montana State University. She briefly lived in San Diego and Butte, Montana before moving to Baker where she raised her children and worked for Fallon County Abstract Company for over 37 years. She cherished the memories of her time in Baker and made many life-long friends. Upon retiring she moved to Castle Rock, CO in 2005, where she enjoyed being closer to family and became an avid fan of the Nuggets, Rockies, and Broncos. She is survived by her daughter Renee Luper - Hackberry, AZ; son Kevin (Kay) Petersen - Castle Rock, CO; four granddaughters, Alicia Zachmann - Coachella, CA, Tierra Zachmann - Palm Desert, CA, Erika Petersen (Alex Schaetzle) - Denver, CO, and Kelsey Petersen (Gavin Madsen) - Johnstown, CO; and Great Grandson, Teddy Schaetzle. Shirley will be laid to rest at Sunset Hills Cemetery in Bozeman, MT.