Amir is guilt-ridden, and several examples of this characteristic come from the book's beginning. When Rahim Khan calls Amir and beckons him back to Afghanistan, he appeals to this trait which he knows Amir possesses by telling him that "there is a way to be good again." He knows that Amir was not at peace with himself when he left Afghanistan and would still not be at peace with himself. However, this attribute is not one that Amir takes on only after the horrific event in Chapter 7. From early on, he feels guilty for his mother's death. He believes that Baba treats him so distantly because he blames Amir for his mother's death. Therefore, Amir goes through the whole novel trying to make up for what he feels he has done. One could argue that if Amir did not possess this trait practically from birth, much of the novel's action would not have taken place.
Amir is also condescending. This is, of course, seen most often in his treatment of Hassan. He allows Hassan to take all the blame for their childhood pranks. He uses Hassan's lack of education to make him the butt of his secret jokes--calling Hassan an imbecile after he has told him that it means "intelligent" (Hosseini 29). Even when he frames Hassan, his superior attitude shows because he believes that he is more worthy of Baba's attention than Hassan is.
Finally, Amir is empty. Even as an infant, he seems to be searching for someone to fill the void that Baba's emotionless parenting has created. He grasps Rahim Khan's in the photograph because he needs someone to hold on to. He tears down Hassan to make him feel better about himself. He constantly goes to his father's study, hoping that Baba will pay him some attention. He tells his father that he might have saracen (cancer), again hoping to get a reaction of any kind. His emptiness, like his guilt-ridden nature, helps the novel's conflict intensify.