755 ILCS 20/3
When the State's Attorney of the county is informed or has reason to believe that any real estate within the county has escheated to the county by reason that any person owning the real estate has died without bequeathing the same, and leaving no heir capable of inheriting the same, or by reason of the incapacity of the legatee to hold the same, and such estate has not been sold according to law within 5 years after the death of the last owner, for the payments of the debts of the deceased, or if the State's Attorney is informed, or has cause to believe that any such estate within the county has otherwise escheated to the county, it shall be the duty of the State's Attorney to file a complaint in behalf of the county in the circuit court of the county, setting forth a description of the estate, the name of the last lawful owner thereof, the names of the parties in possession, and persons claiming such estate, if known, and the fact and circumstances in consequence of which such estate is claimed to have escheated, and alleging that by reason thereof the county has a right by law to such estate. The court shall enter an order against such persons, bodies politic or corporate, as alleged in the complaint, to hold, possess or claim such estate, requiring them to appear at the court on a designated return day, not less than 60 nor more than 90 days after the date thereof, and show cause why such estate should not be vested in the county. A certified copy of the order shall be served at least 10 days before the return day thereof. The court shall set forth in the order briefly the contents of the complaint, and require all persons interested in the estate to appear at the court on the return day so designated and show cause, if any, why the same should not be vested in the county; and the order shall be published for 6 weeks successively in some newspaper printed and published in the county, if any is there published; and if no newspaper is printed in the county, then the notice shall be published in some newspaper in the adjoining county thereto, the last insertion to be at least 2 weeks before the return day on which the parties are required to appear.
755 ILCS 20/3