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.