Illinois Complaint (Child Support) is a legal document used to initiate a child support proceeding in the state of Illinois. It is typically filed by a parent or guardian in order to request the court to order the other parent or guardian to provide financial support for the child. The Complaint details the parties involved in the case, the amount of child support requested, and any additional relevant information. There are three types of Illinois Complaint (Child Support): Petition for Support, Petition to Modify Support, and Petition to Enforce Support. The Petition for Support is used to ask the court to order the other parent to pay child support. The Petition to Modify Support is used to request a change in the amount of child support due. The Petition to Enforce Support is used to ask the court to enforce an existing child support order.