Why do you think the relationship between Baba and Amir is so strained?

THis relationship has been strained since Amir was a child. Amir always felt physically and emotionally weak in the eyes of his father. Amir struggled to be noticed by Baba, he struggled for affection or merely a kind word. As the book goes on, the relationship becomes more complex. The discovery of Hassan as his half-brother puts added stress on both men. Basic expectations between father and son were never met.