(1) If a married couple adopt a child or if a spouse adopts a child of the other spouse, the child attains the legal position of a child of both the spouses.
(2) In the other cases the child attains the legal position of a child of the adoptive parent.
(3) The parental custody is held in the cases governed by subsection (1) by the spouses jointly, and in the cases governed by subsection (2) by the adoptive parent.