(a) A petition for adoption may be filed when the requirements of § 904 of this title have been met, the child is legally free for adoption, and the adoptive placement of the child has been supervised for a period of 6 months by the Department or licensed agency.
(b) In the case of a child to be adopted by a stepparent, guardian, permanent guardian or a blood relative, the petition for adoption shall be filed only after the child has resided in the home of the petitioner for at least 1 year; except that, on recommendation of the Department or licensed agency, a petition may be filed after 6 month's continuous residence of the child in the petitioner's home. In the case of adoption by a stepparent, guardian, permanent guardian or blood relative, it is not necessary that the child be legally free prior to the filing of the petition.