The death of Hassan and Farzana is another stake to the heart of Amir, who blames himself for starting the chain of events that lead to their deaths. Content in their little mud hut in the Hazara village of Bamiyan that was "the only house in the village that had a walled garden," Hassan decided to uproot his family and leave the safety of the village; they returned to war-torn Kabul with Rahim Khan to look after Baba's home in the hope that Baba would one day return. Hassan's loyalty to Baba and Amir would eventually cost him his life: While Rahim Khan is away, the Taliban demand that Hassan vacate the house; Hassan refuses, and both he and Farzana are executed by a man in a herringbone vest. It is yet another example of the undying loyalty that Hassan exhibited toward Amir--loyalty that was never returned by Amir. Hassan's death leads to another series of nightmares for Amir, a bad dream that casts Amir as Hassan's killer:

The rifle roars with a deafening crack.

I follow the barrel on its upward arc. I see the face behind the plume of smoke swirling from the muzzle. I am the man in the herringbone vest.
(Chapter 19)

It is one of the events that convinces Amir to return to Afghanistan to hunt for Hassan's son--and Amir's nephew--Sohrab, the lone survivor of Ali and Hassan's family. Only by rescuing Sohrab and returning him to safety will Amir ever be able to find redemption for his sins against Hassan.