R.I. Gen. Laws § 33-18-18: Intervention in proceedings by or against estate.

If a suit or proceeding be pending, whether instituted by the administrator, executor, guardian, or any legally interested person, then no additional suit or proceeding shall be brought for the same cause, but the administrator, executor, guardian, or any legally interested person, may intervene in the prosecution of the suit or proceeding, upon motion, in the discretion of the court having jurisdiction of the action; and if a suit or proceeding be pending against an administrator, executor or guardian, any legally interested person may, with like consent, intervene in the defense to the suit or proceeding.