In The Kite Runner, what is the connection between blood (kinship) and social relationships?
In the middle of The Kite Runner, protagonist Amir and his wife Soraya discover that they cannot bear a child. Because they both want a child, they consider adoption. Her father, General Taheri, says this:
"Take Amir jan, here. We all knew his father, I know who his grandfather was in Kabul and his great-grandfather before him, I could sit here and trace generations of his ancestors for you if you asked. That's why when his father -- God give him peace -- came khastegari, I didn't hesitate. And believe me, his father wouldn't have agreed to ask for your hand if he didn't know whose descendant you were. Blood is a powerful thing, bachem, and when you adopt, you don't know whose blood you’re bringing into your house."
(Hosseini, The Kite Runner, Google Books)
For the Afghan people, blood-relations are as important as morality and honor. Their understanding of relationships comes from the knowledge of a person's heritage and background. This becomes even more poignant later when Amir discovers that Hassan, who he failed to protect in his youth, was actually his half-brother; this leaves him with even more guilt and shame, because he let fear overcome his responsibility to "his own blood."