750 ILCS 50/12

If, upon the date of the entry of the judgment the person sought to be adopted is of the age of 14 years or upwards, the adoption shall not be made without the consent of such person. Such consent shall be in writing and shall be acknowledged by such person as provided in Section 10 of this Act, provided, that if such person is in need of mental treatment or is a person with an intellectual disability, the court may waive the provisions of this Section. No consent shall be required under this Section if the person sought to be adopted has died before giving such consent.