In Gallagher's book of essay's on Antietam, There is one about the fight in the sunken road with the N.C. brigade. The BG went down. A runner was sent to the senior colonel down at the end of the line. As the sr Col was receiving the order he was hit in the head, KIA. The runner went back found who he thought was in command told him and then that col was hit. It went on more than this and I may not have it exactly right, but you get the point. John