KARL: They told me I was well. Had to turn me loose.
FRANK: Well are you well?
KARL: I reckon I feel all right.
Karl has a childlike honesty in his responses, especially this one. The "are you well?" question is a loaded one that basically means, "Are you going to kill anyone again?" Karl's answer is true…in the moment. Karl also has a childlike ability not to think much about the future.
KARL: You don't need to hear things like that. You just a boy. You need to think about good thoughts while you still a boy. They's plenty of time for all the other.
Karl wants to preserve Frank's innocence, maybe because Karl never had any innocent years of his own.
KARL: Well, I growed up an' learned that you ain't supposed to kill nobody.
Karl killed his mother and her lover without any thought of the consequences, and he did it thinking that it was the right thing to do. Can murder ever be "innocent," in a way?
VAUGHAN: You shouldn't say that. You were taught that, weren't you?
Vaughan corrects Karl for saying he's not funny ha-ha but funny queer. However, Vaughan doesn't get personally insulted by Karl's comment. He knows that mentally, Karl is basically a child repeating something he's been told, in this case by another child—although we imagine Frank heard it from Doyle, making it less than innocent.
FRANK: That makes me feel real sad. Couldn't you have done something, Karl? I would have. I wished I'd had him. He'd still be right here, now. Living.
KARL: It makes me sad too. I wish there was something I could have did about it. I don't think nothing bad oughta happen to children. I think all those bad things oughta be saved up for the folks that done growed up, that's the way I see it. Mmhmm. I shouldn't have told you about that. Boy your age ought not to hear such things. It just kind of come out.
Karl is attempting to do for Frank what many fathers try to do for their children: shield them from bad things. But is attempting to protect children from the realities of the world a parenting method that is itself childish?
KARL: You just a boy. You ought not use language like that.
Because he was raised in a Bible-loving household, Karl has a kind of Puritan innocence. He believes that Frank should have a clean mouth until he reaches an age of maturity. But considering some of the things Frank has seen in his young life, isn't he entitled to a swear word or two?
FRANK: I'm real tired, you know that? A boy my age shouldn't be tired of things.
This line from Frank signals that despite Karl's attempts to preserve Frank's innocence, it's all over. He's already an adult, and at a young age, that is difficult to bear.