Donald “Duff” Carl Duffner, age 80, passed away in the early hours of May 9, 2020, from complications of brain cancer. His wife was at his bedside. A celebration of life with military honors will be held on June 13, 2020, at Crossroads Memorial Church at 11:00 a.m. Don was born on April 7, 1940, in Lewistown. He was the oldest of seven children born to Beulah and Homer Duffner. He joined the US Navy at the age of 17, and spent several years aboard the Destroyer USS Everette F. Larson. Don worked at the smelter, local lumberyards, and retired from the City of Great Falls in 2006. After he returned to Montana, he and Donna Jean Peterson married in 1961, in Lewistown. They had two daughters, Dawn and Debbie. Don was always active with repairing, building something, or working in his shop. He was a quiet person, but felt deeply about his family and friends. After Donna's passing, he and Marcy Adams were married in 2001. They spent many happy days traveling and restoring classic cars. Neighbors never knew what type of car would appear on the driveway as the next project. Several of those vehicles were sold, completed or not, as he would already be looking for a different project. He did complete a 1958 Nash Metropolitan for Marcy and was working on a 1957 Thunderbird when the cancer was diagnosed. Thanks go to several members of the Skunk Wagon Car Club. They worked many hours last summer to complete his T-Bird. Don is survived by his wife, Marcy; daughters, Debbie Johnson and Dawn (Paul) Thompson; step-children, Ed Adams and Amy Paquette; 5 grandchildren; 5 step-grandchildren; 8 great-grandchildren; and 6 siblings. In lieu of flowers, donations to Peace Hospice would be appreciated.