My daughters father is taking me to court to lower his child support. What should I expect? ?

My child father hardley pays what he is supposed to now. He owes me thousands of dollars and is only asked to pay 273$ a month And only pays 14$ sometimes 30$. My daughter does not like to visit them because theres no room for her and she feels unwanted. But I want to know the possibilities that her father will actually get away with this? What will the mediater say? She hasnt been over there in months, but he told her that she can decide whether she wants to go. Plus they want mento provide information that's personal regarding my income. And I want to know what would happen if I did not fill those papers out? I feel that I should not have to because I'm not the one asking for anything, he is? And also I provide absolutely everything for my daughter, with no help. I work my of everyday to provide for her. What should I expect from the mediater?