In this task, you're given passages that contain mentions of names of people, places, or things. Some of these mentions refer to the same person, place, or thing. Your job is to write questions that evaluate one's understanding of such references. Good questions are expected to link pronouns (she, her, him, his, their, etc.) or other mentions to people, places, or things to which they may refer. Do not ask questions that can be answered correctly without understanding the paragraph or having multiple answers. Avoid questions that do not link phrases referring to the same entity. For each of your questions, the answer should be one or more phrases in the paragraph, and it should be unambiguous.
Q: Passage: Lucille, a crippled man who is in a wheelchair from injuries sustained in the Gulf War, searches New Orleans for his friend Melvin so a documentary crew can follow Melvin.  They find him passed out on the street.  Melvin, an alcoholic and drug abuser, is in a downward spiral and spends most of his time partying with his friends.  His estranged ex-wife, Doreen, has filed a restraining order against him and taken sole custody of their young son, Rex.  Lucille wants Melvin to clean up and get sober, but Melvin only makes empty promises to eventually get his life together.
Lucas, a science teacher at the local community college, performs regular tests on Melvin, who has telekinetic powers – the ability to move objects with his mind. Lucas can not explain this except that Melvin has a slightly different brain structure than ordinary people.  Melvin will not see a specialist despite Lucas' urging. Besides Lucas' tests, Melvin uses his powers to perform street shows for drug money.  Lucille, however, blames the local drug dealer, Nathan, of being behind violence in the neighborhood and does not like him.  This is echoed by Jimmy, a local cop.
After a night of hard partying, Melvin's heart stops.  When he wakes, the doctors tell him that he was clinically dead for several minutes.  Changed by this experience, Melvin announces that he intends to become sober for the sake of Rex.  Impressed, Jimmy requests that Melvin help clean up the neighborhood.  After practicing his abilities, Melvin confronts Nathan's gang and threatens them.  Nathan has Lucille shot in retaliation.  After Lucille tells him to leave him alone, Melvin falls back into alcoholism and parties with a friend who was recently released from jail.
A:
Who was Rex's mother once married to?