Throughout their childhood, Hassan and Amir were always at each others side and if anything were to ever happen, Hassan was quick to take the blame to ensure Amir's happiness. In the beginning of the novel, Hassan and Amir are playing together atop a tree and even-though Hassan was reluctant to, decides to shoot at the neighbors dog just to keep Amir happy. Amir knows Hassan's devotion devotion to him and shows it when he says, "I talked Hassan into firing walnuts with his slingshot at the neighbor's dog...Hassan never wanted to, but if i asked,really asked, he wouldn't deny me. He never told that the mirror, like shooting at the neighbor's dog was my idea." (ch.2 pg.3-4). Even though Hassan knew he'd get in trouble afterwards, The love for his brother and attaining his happiness was far more important than the imposing consequence he'd likely receive later. Similarly when the boys enter a kite fighting competition together, they become the winners, and Hassan run's down the kite without a second thought,and ultimately puts his life on the line knowing the happiness the kite brings Amir is worth far more than the pain he is about to suffer. As Hassan gets ambushed in the alley by Assef while trying to retrieve the kite, they get in a fight, " "Whatever you wish"...Assef motioned with his hand and the other two boys separated, forming a half circle trapping Hassan in the alley. "im letting you keep the kite Hazara. I'll let you keep it to remind you of what im about to do to you." "(ch.7 pg.73). Hassan's will to not let Amir down was so greatly valued that he suffered through being brutally raped just to give him a Kite that he believed Amir would cherish greatly. Hassan's brotherly love was always present and because of it, Amir could always count on him to help him in the blink of an eye. Regardless the request, Hassan was always there to carry out what Amir wanted, no matter what he had to endure.
We also see support from Amir's father in the book as he continues to make choices in hopes to benefit Amir's future. Baba makes the tough decision to move to America to ensure a better life for Amir even-though he has to give up the life he once knew and settle for the conditions the new life brings. Amir explains Baba's feelings when he says, " Baba loved the idea of America. It was living in America that gave him an ulcer." (ch.11 pg.125) Knowing that his son would have a better chance at a good life, Baba supports Amir's dream and moves to America in hopes that it will eventually become a reality. He later makes a breakthrough when he finally comes to terms with Amir's want to become a writer and fully supports his decision to fulfill that dream. Baba mentions, " Amir is going to be a great writer... He has finished his first year of college and earned A's in all of his courses." (ch.11 pg.139). Baba's excitement over Amir's success in college acknowledges the fact that he supports Amir and his goals in life which causes Amir to to finally feel a sense of relief and happiness that he now has the backing and approval from his father;which he's been trying to gain for most of his life. Baba went out of his way and comfort zone to be there for Amir and show him how truly proud he is at all he has accomplished, finally allowing him to be happy to gain his father's approval.
Lastly, Sohrab becomes part of the family and in doing so, without knowing it, helps Amir to attain happiness through helping him accept his past, and in a way "make up" / repay Hassan for all that he has sacrificed for Amir in his life. When Amir hears news of Hassan's son, Sohrab, from Rahim Khan,and what has happened to him, he quickly comes to the rescue, feeling obligated to be there like his brother always was for him. Amir expresses his feelings on Sohrab and what he feels he must do,"I was afraid that I'd let the waters carry me away from what i had to do. From Hassan. From the past that had come calling. And from this one last chance at redemption. So I left before there was any possibility of that happening." (ch.18 pg.231). As Amir finds Sohrab and makes the decision to adopt him and save him from his tragic life , he feels relieved knowing that Sohrab is safe and that it's his duty to keep him safe considering all Hassan had done for him. Once Sohrab is finally home and safe with Amir, they decide to go kite fighting and in a moment the two share while flying the kites, all the emotions Amir has felt surface, and causes him to have a feeling of true and utter happiness with Sohrab. Amir asks," Do you want me to run that kite for you? " then explains, " 'for you, a thousand times over' i heard myself say. then i turned and ran.It was only a smile, nothing more. It didn't make everything all right. It didn't make anything right. only a smile. A tiny thing... But ill take it. with open arms... I ran with the wind blowing in my face, and a smile as wide as the valley of Panjsher on my lips." (ch.25 pg.371). With something as small as a simple request, Sohrab had no idea that he helped support Amir in coming to terms with his past and finally being happy like he and Hassan once were all because of the company of his new son. Sohrab's love finally causes Amir to be able to begin to move on from his past and accept what has happened.. With Sohrab now being part of the family and serving as a daily reminder of all the joy Hassan brought, he serves as a vital part of support in Amir's journey to finally reaching happiness through help from his family all along the way.