The characters that change or develop the most in Khaled Hosseini's A Thousand Splendid Suns are Mariam and Laila, the two protagonists who must grow and adapt to cope with their often difficult circumstances.

Mariam is an illegitimate child who grows up in her mother's hut and nearly idolizes her father. However, Mariam learns at a fairly young age that her father will never treat her the same way as he does his legitimate children. In fact, he disappoints her badly on her fifteenth birthday, and not long after, Mariam is forced to marry the abusive (and much older) Rasheed. From there on out, Mariam must learn how to cope with many things. She has to deal with her husband's abuse, her inability to conceive a child, and the arrival of Laila as Rasheed's second wife. Mariam must either develop her strength or die. She chooses the former, so much so that she is able to defend Laila from Rasheed, killing him in the process, and accept her punishment without regret.

Laila, too, develops greatly over the course of the novel. She is an educated girl from a good family, but her mother is cold to her. Laila loves Tariq, but he goes off to fight. Her family faces tragedy when her brothers are killed, and later, her parents die in a rocket attack that almost takes Laila's life as well.

Mariam finds Laila and takes care of her, and then Rasheed marries her. Laila has no choice in the matter, and she has to learn how to get along in a whole new life. Laila becomes pregnant and has a daughter, much to Rasheed's disgust, and from there, Laila and Mariam develop a close relationship. The two women grow together and try to escape from Rasheed, only to be caught. Eventually, Laila has an opportunity for freedom when Mariam kills Rasheed, and she joins Tariq to start a new life.

Indeed, these two women have had to change and develop to meet their circumstances and to survive. They learn and grow together, and only Laila still lives by the end of the novel, but she will always remember the lessons Mariam taught her about courage and love.

What minor character reveals development traits/progress for a main character in A Thousand Splendid Suns and the themes the character represents?

There are quite a few characters of interest that could have been expanded to larger roles by the author in A Thousand Splendid Suns. Perhaps the most fascinating character is Jalil, Mariam's father. Jalil plays a major role in the opening chapters before all but disappearing during the remainder of the novel. He is obviously a loving, well-educatad man who has been caught up in a situation which he must keep distant from the rest of his larger family. He loves his bastard child, Mariam, but because of Afghani society's restraints (and the apparent disapproval of his three wives), he refuses to accept her as a true member of his family. His weakness in allowing his wives to send Mariam into a contract marriage with an older man in a distant city is deplorable, and this act haunts Mariam--and Jalil--forever.

Later in the novel, Jalil seeks redemption, waiting for hours outside Rasheed's home in Kabul in the hope of seeing his daughter one last time. But, like Jalil's refusal to admit Mariam into his home on her visit there, Mariam likewise refuses Jalil's admittance. She will never see him again, and only much later do we find that Jalil is dying and hopes to see his special daughter one last time. It is Laila who eventually discovers this truth when she returns to Mariam's home in the final chapters.

Jalil is a tragic character. In addition to losing Mariam, he suffers great financial losses during the Russian takeover as well as the death of several family members during the years of war. His attempt to atone for his mistakes is never known to Mariam, who once again hears the terrible word harami--bastard--as she is about to be executed. Jalil's memory and final wishes will be forever ingrained within Laila, however, and his gift of the money meant for Mariam will help Tariq and Laila begin a new life in Kabul.