(a) The parent of an unmarried incapacitated person may appoint by will, or other writing signed by the parent and attested by at least two witnesses or acknowledged, a guardian of the incapacitated person. If both parents are dead or the surviving parent is adjudged incapacitated, a parental appointment becomes effective when, after having given seven days' prior written notice of intention to do so to the incapacitated person and to the person having the care of the person or to the nearest adult relative residing in this state, the guardian files acceptance of appointment in the court in which the will is probated, or in the case of a nontestamentary nominating instrument, in the court at the place where the incapacitated person resides or is present. If both parents are dead, an effective appointment by the parent who died later has priority.

(b) The spouse of a married incapacitated person may appoint by will, or other writing signed by the spouse and attested by at least two witnesses or acknowledged, a guardian of the incapacitated person. The appointment becomes effective when, after having given seven days' prior written notice of intention to do so to the incapacitated person and to the person having care of the incapacitated person or to the nearest adult relative residing in this state, the guardian files acceptance of appointment in the court in which the will is probated or, in the case of nontestamentary nominating instrument, in the court at the place where the incapacitated person resides or is present. An effective appointment by a spouse has priority over an appointment by a parent.

(c) An appointment effected by filing the guardian's acceptance under a will probated in the state of the decedent's domicile is effective in this state.

(d) Upon the filing in the court in which the will was probated or, in the case of a nontestamentary nominating instrument, in the court at the place where the incapacitated person resides or is present, of written objection to the appointment by the incapacitated person for whom a parental or spousal appointment or guardian has been made, the appointment is terminated. An objection does not prevent appointment by the court in a proper proceeding of the parental or spousal nominee or any other suitable person upon an adjudication of incapacity in proceedings under the succeeding sections of this division.