You are facing serious allegations that can have long term consequences with regard to your access to your children. I highly recommend consulting an experienced family law attorney who practices in the county where the suit is. Many attorneys offer free consultations.
OP's are liberally granted in Illinois, and it may be a tactical move to set up her dissolution case (Insofar as it relates to custody). Most people get blind-sided by this tactic and respond a day late and a dollar short. After ex's lock in temporary custody, they usually move for dissolution & temporary child support (And likely maintenance, which is what Illinois calls Alimony). By the time you realize what's going on, game over.
Consider talking to a family law attorney before you find yourself living in a van down by the river. Venue may sit in Will County (Not enough information to know for sure) - but if you don't properly object, you waive that issue.
Yes, I think you should have an attorney represent you at the hearing. Look for a local family law attorney who has handled many order of protection cases in the past. If you need a referral, feel free to give me a call. 1-800-517-1614.
You should definitely have an attorney. Often an Order of Protection is a tactical move to get Exclusive Possession of the marital residence or custody before filing for divorce. There are other negative implications to having an Order of Protection against you.