Idaho Code § 5-306: Infants and insane persons — Guardians ad litem.

When an infant or an insane or incompetent person is a party, he must appear either by his general guardian or by a guardian ad litem appointed by the court in which the action is pending in each case. A guardian ad litem may be appointed in any case when it is deemed by the court in which the action or proceeding is prosecuted, or by a judge thereof, expedient, to represent the infant, insane or incompetent person in the action or proceeding, notwithstanding he may have a general guardian and may have appeared by him.