5.—It is hereby declared that, in relation to a child, any reference to “father”, “mother” or “parent” in the Irish Nationality and Citizenship Acts, 1956 and 1986, includes and shall be deemed always to have included the father, mother or parent, as the case may require, who was not married to the child’s other parent at the time of the child’s birth or at any time during the period of ten months preceding the birth.