How does the tone of the novel change at the beginning of this chapter now that Baba and Amir live in the U.S

The tone changes to a much more resigned and wounded feeling where we see how much Baba has given up in order to ensure Amir a better future. Once a party-giver and benefactor, Baba is now a gas-station worker in a country where he does not even speak the language fluently. He has gone from living in a large, luxurious house to living in a small apartment. Once the person everyone else could depend on, Baba now depends on Amir to help him navigate American life.