Instead she tells Adam it's wrong to kill. It's nice to see Adam getting some instruction in ethics, but at this point it's a bit late. Adam didn't ask her, "If it's wrong to kill, then how come Barnabas was going to kill me? How come Harry was going to kill me?"
Then Carolyn could tell him they were wrong. What parent (or teacher) hasn't come across the situation where they are explaining that something is wrong to a child who answers, "But so-and-so does it"? For parents that argument is irrelevant because it's their job to set moral standards for the child regardless of what her or his peers might be doing. And Adam is nothing if not an over-sized child. Hey, B & J and Carolyn, nobody says parenting is easy.
Who here, when you were growing up, has heard, "If Jenny/Tommy jumped off a cliff, would you do it too"? I'd love to hear my mother say THAT to Adam, who has, you know, actually jumped off one.
He's seen a lot of confusing things in his life.
Poor Adam. Another crazy part in this situation is that Adam HAS killed someone. (I know several here disagree over who is responsible for Sam's demise, but Adam believes himself responsible for his friend's death, and other characters on the show have often placed the blame squarely on Adam's big shoulders.) But how does Carolyn deal with it? Does she tell Adam that he has to turn himself into the police, confess to what he did, and accept punishment for it? Does she or anyone else encourage him to talk about what happened, to express his remorse, or to apologize to Sam's loved ones? No and no. Instead, the lesson seems to be that killing another person is wrong, but if you do it we will hide you away, sneak you food, continue your education in private, and avoid talking about the incident as much as possible.
BTW, I don't think killing Harry could have been considered self-defense. Once Adam completely disarmed him, harming him was not justified by the law since Adam was no longer in imminent danger, and it would not have been morally right to kill him either.
I hope to be cremated when I die, and watching Dark Shadows confirms me in this plan. Golly, the dead never get a minute to themselves around Collinsport! Except for Jason McGuire, and that's only because very few people know that he's dead.
Har!