Lt. Colonel Maes Hughes
From Animepedia
Lieutenant Colonel Maes Hughes is Ed and Al's good friend in the military. He is shrewd and very intelligent. However, there is a very different side to his serious personality. He absolutely loves his family, and talks about them every spare moment he has. He is constantly showing everyone pictures of his daughter, Elycia, and his wife, Gracia. It is clear that he loves his family very much. Hughes is the first one to notice that things are not quite right in the military. When he begins to dig deeper, he finds out some things he shouldn't. Ultimately, that leads to his death at the hands of Envy, a homunculus. Upon his death, Lieutenant Colonel Hughes is promoted to the rank of Brigadier General, as noted on his tombstone.