In chapter 25, Amir brings his adopted son, Sohrab, home with him to California, where Sohrab has a difficult time adjusting to his new life. After enduring such extensive trauma as a child, Sohrab refuses to speak, and his silence is depicted as being forced and oppressive. Amir begins by describing the positive aspects of silence by saying,

"Quiet is turning down the VOLUME knob on life. Silence is pushing the OFF button. Shutting it down. All of it." (Hosseini, 392)

This type of voluntary silence is tranquil, peaceful, and rejuvenating. It is the typical silence individuals seek when they need time to heal, rest, and reflect. Amir then juxtaposes this type of calm, soothing silence with Sohrab's oppressive, harsh silence by saying,

"Sohrab's silence wasn't the self-imposed silence of those with convictions, of protesters who seek to speak their cause by not speaking at all. It was the silence of one who has taken cover in a dark place, curled up all the edges and tucked them under." (Hosseini, 392)

Sohrab's silence is designed to remove him from the world as if he was hiding from something hostile or threatening. Both Amir and his wife have difficulty accepting Sohrab's suffocating silence, which becomes a dark cloud over their daily lives. Amir goes on to mention that Sohrab simply occupied space in their home and was aware that other people barely noticed his presence.

     Quiet is peace. Tranquility. Quiet is turning down the volume knob on life.
     Silence is pushing the off button. Shutting it down. All of it.  (Chapter Twenty-Five)

This quote describes the peacefulness of most people during their quiet time. Such is not the case with Sohrab. Sohrab's silence is not of a tranquil nature. It is the forced silence

... of one who has taken cover in a dark place, curled up all the edges and tucked them under.  (Chapter Twenty-Five)

Sohrab still has not spoken since coming to live in California. He has withdrawn into his own little world--sitting, staring, sleeping. It is not a life, but only a means to "occupy space," and "While Sohrab was silent, the world was not." The Twin Towers "came crumbling down," and "Sohrab sleepwalked through it all." The terrorist attacks on 9/11 provide Amir and Soraya with an outlet to display their renewed patriotism for both Afghanistan and America, but Sohrab's silence leaves little happiness in Amir's household. It is the silence of fear and bad memories that cannot be erased by pressing the delete button.