Illinois Statutes Chapter 750. Families § 50/2. Who may adopt a child

(a) A reputable person of legal age and of either sex, provided that if such person is married or in a civil union and has not been living separate and apart from his or her spouse or civil union partner for 12 months or longer, his or her spouse or civil union partner shall be a party to the adoption proceeding, including a spouse or civil union partner desiring to adopt a child of the other spouse or civil union partner, in all of which cases the adoption shall be by both spouses or civil union partners jointly;

(b) A minor, by leave of court upon good cause shown.

(c) Notwithstanding sub-paragraph (a) of this subsection, a spouse or civil union partner is not required to join in a petition for adoption for the adoption of an adult if a petitioner is a former stepparent of that adult, or to re-adopt a child after an intercountry adoption if the spouse or civil union partner did not previously adopt the child as set forth in subsections (c) and (e) of Section 4.1 of this Act. For purposes of this Section, “former stepparent” means a person who was married to, or in a civil union with, the legal parent of the adult seeking to be adopted, and the marriage or civil union has ended.

(a) an adoption of a related child;

(a-1) an adoption of a child previously adopted in a foreign country by the petitioner;

(b) an adoption of a child placed by an Illinois-licensed child welfare agency performing adoption services;

(c) an adoption of an adult by a former stepparent; or

(d) an adoption of a child born in this State who has resided continuously in this State since birth, or a child who has continuously resided in this State for at least 6 months immediately preceding the commencement of the adoption proceeding, if: