Despite being a children's classic, The Adventures of Tom Sawyer does feature a few deaths.
Dr. Robinson is stabbed to death by Injun Joe in a graveyard. He, Injun Joe, and Muff Potter are all in the graveyard because the doctor wants them to dig up a corpse for medical experimentation purposes. Injun Joe frames Muff Potter for the crime. Robinson's death is what incites the conflict between Injun Joe and Tom, since Tom witnesses the killing and knows Potter is innocent.
Injun Joe himself also meets a rather grisly end. Tom and Becky are trapped in the cave, running low on food, candles, and other supplies. During this time, they realize Injun Joe is in the cave as well, using it as a hideout. When the two children make it out of the cave and return home, Judge Thatcher has the cave sealed up with a heavy door. It is not until Tom recovers from his physical exhaustion two weeks later that he informs the adults that Injun Joe was in the cave as well. When the door is removed, the townspeople find Injun Joe lying dead from starvation. His death is an apt metaphor for his status as a social outsider cut off from other people.