3. Only the following persons may adopt a child:(a) consorts living together;
(b) the new consort of the father or mother of a legitimate child;
(c) consorts judicially or de facto separate as to bed and board, or one of them, if they have adopted the child de facto prior to their separation;
(d) an unmarried person, provided that the child is of the same sex as such person.
Nevertheless, the court may grant the adoption notwithstanding the difference in sex between the adopted child and the adopter if the latter is the father or mother or another ascendant of the child or if such adopter is a widow or widower who had already adopted the child de facto before the death of his or her consort.