>> reporter: they happened to spend time with the unit that was ambushed and everyrun in knee jeer a month before they did this. they have access to how the shoulders lived their lives before they were killed. with la david johnson he's the father of two, his pregnant widow, had that spat with president trump, you really see how he lived and his personality came through. this was sergeant la david johnson a month before hi death. the video shot showed his mood light. >> whose next. >> reporter: personality contagious. >> keeping the regulations. >> reporter: describing his duties in a makeshift barbershop. >> regular maintenance on the knee. >> reporter: johnson and three other soldiers died in an ambush. asked if he received proper training, johnson couldn't think