No person other than the parents or relatives may assume the permanent care and custody of a child under 14 years of age unless authorized so to do by an order or decree of court. However, if a parent of a child who is being cared for by a relative dies, or if the parent is not or cannot fulfill parental duties with respect to the child, the relative may bring a petition under section 260C.141. Except in proceedings for adoption or by a consent decree entered under section 257C.07, no parent may assign or otherwise transfer to another parental rights or duties with respect to the permanent care and custody of a child under 14 years of age. Any such transfer shall be void.