Mark Sidler

Mark Dennis Sidler, born October 15, 1956, at March Air Force Base in Riverside, California, passed away March 10, 2026, in Joplin, Missouri.

Mark spent his early years in California before moving in his forties to Kansas City, where he embraced his role as a devoted grandfather. A machinist by trade, he was respected for his strong work ethic and his habit of arriving thirty minutes early for work and nearly every other commitment. He found joy in life’s simpler pleasures and possessed a big heart, especially for children. He cherished his grandchildren, Mason and Aubry, and delighted in sharing with them the same sense of wonder he had known since childhood. His early fascination with blowing things up evolved into a lifelong passion for rockets and space shuttle launches, which he passed on by building and launching toy rockets with his grandchildren. He also loved taking them to the circus, on toy train rides, and to see bright neon lights, and he enjoyed the thrill of motorcycle riding and NASCAR.

Mark is survived by his loving wife of 42 years, Mary Sidler; his children, Philip Keegan and Jo-Lynn Kleinsorge; his grandchildren, Mason Kleinsorge and Aubry Kleinsorge; his brothers, Larry Sidler and Steve Sidler; his niece, Jessica Lopez; and many loved nieces and nephews. He was preceded in death by his parents, Jerry and Millie Sidler; his brother, Jeff Sidler; and his sister, Debra Martinez.

A private family memorial will be held at a later date.