Chapter 4 relates the story of how Ali came to be a servant in Amir's household. Accordingly, in 1933, a Hazara man and his wife were killed in a car accident on the road to Paghman. The two young men responsible for the crash were ordered to serve a year in the army at Kandahar. Meanwhile, the couple's five year old son, Ali, was adopted into the household of Amir's grandfather.
Ali grew up with Amir's father, Baba, the same way Amir grew up with Hassan (Ali's son) a generation later. Despite this warm and intimate generational friendship, Amir confesses that neither he nor Baba have ever referred to Ali and Hassan as friends. Amir laments that the divide engendered by the demands of history and religion may be impossible to overcome. Despite this, he insists that the special childhood bond between him and Hassan will ever hold a value all its own. He reminisces fondly about their boyhood games, their strolls through bazaars, their foray into Western cinema, and their glee in spending their pocket money on local treats.
As Amir's servant, Hassan is responsible for completing all Amir's chores. After school each day, both boys habitually find their way to a nearby, abandoned cemetery. There, Amir would read aloud to Hassan. Amir theorizes that Hassan's illiteracy may be the main impetus behind his fascination with the written word. Despite knowing this, Amir is not above playing pranks on his servant. With Hassan none the wiser, he deliberately misrepresents the meanings of difficult words on a fairly common basis.
Amir notes that Hassan is often filled with emotion at the reading of his favorite story, Rostam and Sohrab. In the story, Rostam manages to kill his nemesis, Sohrab, only to discover that he has killed his long-lost son. Amir is curious as to whether Hassan weeps for the father or the son. He does not think of Rostam's fate as especially tragic, as he believes that all fathers secretly view their sons as competitive adversaries on some level.
One day, Amir plays another prank on Hassan, but this time, it is in the form of pretending to read from a book while making up a story-line as he proceeds. Hassan tells him that it is the best story Amir has ever read to him. Elated, Amir proceeds to write a short story. Upon completion of his story, Amir seeks out Baba, hoping that his father will read it. However, Baba's insulting lack of enthusiasm greatly hurts Amir. Baba's friend, Rahim Khan, makes up for Baba's indifference. He asks for the story so that he can read it for himself; later, he writes an encouraging note to Amir.
In the letter, Rahim Khan tells Amir that his gift for instilling irony into a story is an enviable gift many other writers have struggled to attain throughout their writing careers. He encourages Amir to continue writing. Ecstatic at this positive response from Rahim Khan, Amir reads his story to Hassan, who also displays great enthusiasm. Hassan insists that Amir will become famous one day.
Interestingly, it is Hassan who unwittingly draws Amir's attention to a flaw in his writing. Despite bristling at his servant's boldness, Amir tries to craft a response. However, he tells us that he never really gets to finish his words; the chapter ends with Amir's ominous declaration that Afghanistan was soon to change forever.