765 ILCS 45/13

Any person interested may oppose any such petition, and file his answer or appropriate motion thereto on or before the day named in said publication notice, unless the time be extended by order of court, and may also file a cross petition if he or she desires to do so. Such answer shall admit or deny all the material allegations of the petition, and shall, except when made by guardians ad litem, be verified by the affidavit either of the respondent or his agent, in the same manner as above required on cases of the petition. The answer shall have no other nor greater weight as evidence than the petition.