(a) If the owner of the property or of any interest therein is a minor or under any disability whatsoever, notice of condemnation shall be served upon his personal representative.

(b) If there is no personal representative, notice shall be served personally on the minor and on the judge of the probate court of the county where the property or interest is located. The judge shall thereupon appoint a guardian ad litem to represent the minor in the litigation.

(c) If the judge of the probate court is disqualified, by reason of interest or other cause, notice shall be served on the clerk of the superior court of the county where the property or interest is located, who shall appoint a guardian ad litem to represent the minor.