If a parent of the child has not been personally served in a suit in which the Department of Family and Protective Services seeks termination, the court that terminates a parent-child relationship may not appoint the Department of Family and Protective Services as permanent managing conservator of the child unless the court determines that:
(1) the department has made a diligent effort to locate a missing parent who has not been personally served and a relative of that parent; and
(2) a relative located by the department has had a reasonable opportunity to request appointment as managing conservator of the child or the department has not been able to locate the missing parent or a relative of the missing parent.