Col. Alfred Flowers, 99th Medical Group commander, and U.S. Army Staff Sgt. Michael O’Callaghan reveal a portrait of O’Callaghan during a ceremony celebrating the Mike O’Callaghan Military Medical Center’s 25th Anniversary on Nellis Air Force Base, Nevada, Nov. 12, 2019. The portrait will hang in the MOMMC to honor the centers namesake. (U.S. Air Force photo by Senior Airman Kevin Tanenbaum)