Who is Infantryman Yoder from The Killing Zone: My Life in the Vietnam War and what is their importance?

Yoder is a soldier in Lt. Downs' platoon. He is described as somewhat of a hillbilly and missing a front tooth. He is also a big man, over six feet tall, and from a large family. Yoder makes a lot of jokes with Lt. Downs and is a very dependable soldier. He is leading the point, the forward element of the platoon, when he is ambushed. Yoder is shot, and it is impossible despite an attempt, to rescue him. Yoder is shot again and becomes the first soldier under Lt. Downs' command to be killed in action.