A. An action to declare a successor unworthy may be brought only by a person who would succeed in place of or in concurrence with the successor to be declared unworthy, or by one who claims through such a person.
B. When a person who may bring the action is a minor or an interdict, the court, on its own motion, or on the motion of any family member, may appoint an attorney to represent the minor or interdict for purposes of investigating and pursuing an action to declare a successor unworthy.