Country music singer Mindy McCready's reportedly abusive ex-boyfriend is demanding a paternity test to determine whether or not he is the father of her six-month-old son. Billy Mcknight claims MCCready wants him to be a proper father to son ZANDER, but he says he has serious doubts about whether the boy is his biological child. MCKnight served 30 days in jail for abusing MCCready after being arrested and charged with attempted murder after a domestic dispute in May 2005. MCCready learned that she was pregnant last summer (05) and admitted she tried to kill herself with prescription medication in a Florida hotel room. She gave birth to her son in March (06) and now is even considering reconciling with MCKnight. MCKnight says isn't sure he's the father, but is more than willing to step into the role if he has proof of paternity. He tells American publication National Enquirer, "She took off with a con artist when I was in jail, and I don't know what was going on in her life at the time. "She wants me to be a father to Zander and has even talked to me about getting back together as a family. "I look forward to it, but I have to know for sure the child is mine."