No order to sell real property shall be granted until the heirs and devisees of the decedent have been made parties to the special proceeding by service of summons in the manner required by law, in accordance with G.S. 1A-1, Rule 4. Upon such service, the court shall appoint a guardian ad litem for heirs and devisees who are unknown or whose addresses are unknown, and summons shall issue to the guardian ad litem as such. The guardian ad litem shall file answer for such heirs and devisees and defend for them, and the guardian ad litem shall be paid such sum as the court may fix, to be paid as costs of the proceeding.
N.C. Gen. Stat. § 28A-17-4