Calvin O. Robertson, 81, of Joplin, Missouri, passed away on Monday, July 20, 2026, surrounded by his loving family after a long illness. Calvin was born on November 25, 1944, in Carthage, Missouri, to Leonard and Janetta (Dougan) Robertson. A lifelong resident of the area, he dedicated 44 years to Tri-State Motor Transit, where he retired as Vice President of Operations. During his career, Calvin helped establish a Student of the Month partnership between Tri-State Motor Transit and Duenweg Elementary School. Additional survivors include two sons, Dustin Robertson of Springfield, Missouri, and Matt Robertson and wife, Karen, of Carl Junction, Missouri; and four beloved grandchildren: Callyn, Ethan, Bennett, and Laney.