There are a couple of different scenarios where this issue might arise, and each one is treated differently. In one scenario, the person you are trying to obtain child support from may not live in Illinois, and may have never lived in Illinois. However, if you can prove that you went to Illinois for various reasons that are written into the long arm jurisdiction statute, including going to Illinois at the direction of the person you are trying to obtain child support from, you may be able to obtain a child support order in Illinois. However, the support order would have to be sent to the state where the person currently resides for enforcement. Many states have programs similar to Illinois which employ states attorneys to collect child support from child support obligors. They can enforce an order entered by another state.
Additionally, if the person you are trying to collect child support from lived in Illinois and was involved in your legal case in Illinois, and then moved, but you still reside here, the courts in Illinois still have jurisdiction over that individual to modify support, enter judgments on arrearages, and more. You may be able to enter an order in Illinois modifying the child support obligation even if the person no longer lives here.
Of course, in situations that deal with multi-state parties, the procedure on how to handle this is very circumstantial and depends upon the various factors involved. Every case is unique, and our attorneys are eager to assist in these matters should you have questions regarding whether or not you can file for support in Illinois.