The attorney at law appointed to represent an absent heir or legatee shall:
(1) Make all necessary efforts to determine the identity and address of the absent heir or legatee, and to inform him of the death of the deceased and of his interest in the succession;
(2) Represent the absent heir or legatee in the succession, and defend his interests in all contradictory proceedings brought against him therein; and
(3) Take any conservatory action necessary to protect the interests of the absent heir or legatee, including the filing of all necessary suits.