Life as an immigrant is difficult.
For an immigrant, and especially for a refugee, life is incredibly complicated and difficult. Something like a broken tail light wouldn't bother an established citizen, but for the Ahmetis family, it's literally life-changing and deadly. This is because there are serious breaches between American cultures and other cultures of the world which unfortunately means that American culture is often averse to foreigners. This is all demonstrated in the Ahmetis family around whom the novel centers.
Life with PTSD is brutal and continually traumatic.
For the characters who don't treat their mental illnesses, their paranoia is their downfall. When two equally traumatized people encounter each other, the skittish interaction leads to the wrongful death of an innocent woman. This continual re-traumatizing is part of PTSD, since PTSD makes its victim incompatible with the world, and therefore continually subject to the world's cruelty.
Mental health can be attained through therapy.
By facing problems head on like Luis, and by trying to make up for past wrong-doings, life can be made better, especially with the help of a serious professional who can guide the rehabilitation process toward mental health. Luis's story is the positive version of Nate and Sardik's negative example. His character is an indication that the novelist believes therapy is helpful and sometimes necessary.
Abuse and broken homes.
Roberta's insight as a seasoned social worker comes in handy in the novel. She is talented at her job and her work helps illustrate the tragic reality of families destroyed by untreated mental illnesses.
