Whenever the claim or defense asserted in the amended pleading arose out of the conduct, transaction, or occurrence set forth or attempted to be set forth in the original pleading, the amendment relates back to the date of the original pleading. An amendment changing the party against whom a claim is asserted relates back if the foregoing provision is satisfied and, within the period provided by law for commencing the action against the party, the party to be brought in by amendment (1) has received such notice of the institution of the action that the party will not be prejudiced in maintaining a defense on the merits, and (2) knew or should have known that, but for a mistake concerning the identity of the proper party, the action would have been brought against the party. The relation back of an amendment joining or substituting a real party in interest shall be as provided in Rule 202. The delivery or mailing of process to the Idaho attorney general or designee of the attorney general, or an agency or officer who would have been a proper respondent if named, satisfies the requirement of clauses (1) and (2) hereof with respect to the state of Idaho or any agency or officer thereof to be brought into the action as a respondent.
Id. Fam. Law. P. 216