Idaho Statutes Title 15. Uniform Probate Code § 15-5-301. Testamentary appointment of guardian for incapacitated person or developmentally disabled person

(a) The parent of an incapacitated person or developmentally disabled person may by will appoint a guardian of the incapacitated person or developmentally disabled person. A testamentary appointment by a parent becomes effective when, after having given seven (7) days' prior written notice of his intention to do so to the incapacitated person or developmentally disabled person and to the person having his care or to his nearest adult relative, the guardian files acceptance of appointment in the court in which the will is informally or formally probated, if prior thereto, both parents are dead or the surviving parent is adjudged incapacitated. If both parents are dead, an effective appointment by the parent who died later has priority unless it is terminated by the denial of probate in formal proceedings.

(b) The spouse of a married incapacitated person or developmentally disabled person may by will appoint a guardian of the incapacitated person or developmentally disabled person. The appointment becomes effective when, after having given seven (7) days' prior written notice of his intention to do so to the incapacitated person or developmentally disabled person and to the person having his care or to his nearest adult relative, the guardian files acceptance of appointment in the court in which the will is informally or formally probated. An effective appointment by a spouse has priority over an appointment by a parent unless it is terminated by the denial of probate in formal proceedings.

(c) This state shall recognize a testamentary appointment effected by filing acceptance under a will probated at the testator's domicile in another state.

(d) On the filing with the court in which the will was probated of written objection to the appointment by the person for whom a testamentary appointment of guardian has been made, the appointment is terminated. An objection does not prevent appointment by the court in a proper proceeding of the testamentary nominee or any other suitable person upon an adjudication of incapacity in proceedings under the succeeding sections of this part.

(e) If the appointment by will is for a developmentally disabled person and there is an existing guardianship proceeding under chapter 4, title 66, Idaho Code, in which the decedent was the sole guardian, the guardian appointed by will must also give seven (7) days' written notice of his intention to file an acceptance of appointment to any then serving guardian ad litem for the developmentally disabled person in such proceeding and to the department of health and welfare for the region in which the proceeding was brought.

(f) If the appointment by will is for an incapacitated person for whom there is an existing guardianship proceeding in which the decedent was the sole guardian, the guardian appointed by will must also give seven (7) days' written notice of his intention to file an acceptance of appointment to any then serving guardian ad litem for the incapacitated person in such proceeding.