An original suit requesting only an adoption or for termination of the parent-child relationship joined with a petition for adoption may be filed by:
(1) a stepparent of the child;
(2) an adult who, as the result of a placement for adoption, has had actual possession and control of the child at any time during the 30-day period preceding the filing of the petition;
(3) an adult who has had actual possession and control of the child for not less than two months during the three-month period preceding the filing of the petition;
(4) an adult who has adopted, or is the foster parent of and has petitioned to adopt, a sibling of the child; or
(5) another adult whom the court determines to have had substantial past contact with the child sufficient to warrant standing to do so.