A hearing my be conducted by a judge in court or by the Department of Healthcare and Family Services.
If paternity has not been established, you may be asked personal questions about the circumstances surrounding conception.
You will be asked questions about your finances in an effort to determine the amount of child support to be paid.
Pertinent information includes your marital status, number of children, employment status, income and expenses.
https://www2.illinois.gov/hfs/ChildSupport/parents/Pages/FAQs.aspx#hearing