Task: Question Answering
Input (English): 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. 
Question: What motivation does Doreen's ex-husband have for performing on the street?
Output (English): drug money.