As a youth, Amir is too immature to understand the relationship his father has had with his Hazara servants, Ali and Hassan. Amir cannot bring himself to call Hassan his "friend" because of their social differences; and, indeed, Baba never calls Ali his "friend," either. But Baba recognizes his responsibility to take care of his old playmate, and when Ali decides to leave following the accusation of theft against his son, Baba begs him to stay. Baba is an honorable man of the highest caliber. When his growing wealth allows him to do so, Baba builds an orphanage to house children who, like Ali, had lost their parents. At the risk of his own life, Baba stands up to the Russian soldiers who want to rape one of the woman passengers before being allowed to continue on their voyage out of the country.
"Tell him I'll take a thousand of his bullets before I let this indecency take place," Baba said.
Baba's moral responsibility may have failed him momentarily when he fathered Sanaubar's child, Hassan, but he made up for his indiscretion by caring for the boy--although discreetly and at a distance. It is Baba's one great sin--"There is no act more wretched than stealing" he once tells Amir--and he believes he has taken this secret to his grave.
When Amir reaches adulthood, he is finally able to accept some of the moral responsibilities that eluded him as a child. He forgives the past indiscretions of his wife-to-be, Soraya, and courts her in the proper Afghan way. Amir and Soraya tend to Baba's every need during his final days, and following Baba's death, Amir grows into a successful writer and husband. Yet when the phone call from Rahim Khan comes, promising him that "there is a way to be good again," Amir reluctantly jumps at the chance to return to Afghanistan to find Sohrab--a way to alleviate his guilt for his sins against Hassan and provide a safe haven for the boy who Amir discovers is his own nephew. No brave man like his father, Amir nevertheless summons the courage to undertake the dangerous trip back into Taliban-held Afghanista, where he risks his life to find and free Sohrab. When Amir discovers that there is no one in Pakistan to care for Sohrab as Rahim Khan has promised, he decides to take Sohrab back home to California with him: It is the least he can do for his nephew and to honor the memory of his faithful kite runner, Hassan.