After recovering from the beating he endures in order to rescue Hassan's son Sohrab, Amir develops a scar on his lip which resembles the scar Hassan had born since childhood, also on his lip. This is both ironic and symbolic. Amir's new scar makes him more like Hassan, just as his rescue of Sohrab makes him more like Hassan: Amir rescued Sohrab from Assef, just as Hassan once had rescued Amir from Assef. To further the irony, it is with his slingshot that Sohrab saves Amir from being beaten to death by Assef, just as his father also had used his slingshot to save Amir from Assef many years before. Amir's scar becomes a badge of honor and courage. He is no longer isolated by the shame and guilt he had carried with him since he and Hassan had been children together.
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