In Soldiers Heart by Gary Paulsen, a boy named Charley signs up for the army even though he is supposed to be 21 and he is only 15. When he is training for the war all he can eat is beans and salted pork. When he sets out to fight the Rebels they go to war very quickly. Many of Charly's freinds are injured or killed.  The next day they go to war again and when Charley is retreating again he finds his good friend shot and is mumbling. Charley tries to get a surgeon over but there is nothing the surgeon can do about belly wounds. That night while Charly is on watch for the Rebels a boy from the Rebels wants to trade with Charly so they make a trade. Then the next battle a man tells Charly he needs to go to the tent because he was shot. It turns out he wasn't shot but there are many men that are dying and really wounded. After the war is over he comes home but he is on a cane and he is not interested in finding a girl or having kids.