(a) Subject to subdivision (b), “interested person” includes any of the following:
(1) An heir, devisee, child, spouse, creditor, beneficiary, and any other person having a property right in or claim against a trust estate or the estate of a decedent which may be affected by the proceeding.
(2) Any person having priority for appointment as personal representative.
(3) A fiduciary representing an interested person.
(b) The meaning of “interested person” as it relates to particular persons may vary from time to time and shall be determined according to the particular purposes of, and matter involved in, any proceeding.