Section 37. If an executor, administrator, guardian, conservator, trustee, receiver, commissioner, or other fiduciary officer, appointed by any court is the ward of a guardian, conservator or committee, or other like officer, appointed by any court in this commonwealth, or by any court at the place of his domicile, to have charge of his property or his person, such guardian, conservator or committee, or other like officer, may, on behalf of the ward, resign the trust or other office held by the ward if the court which appointed the ward finds it proper to allow such resignation, and the court may accept such resignation without notice to the ward. In the case of a fiduciary under a written instrument who was not appointed by a court, his guardian, conservator or committee, if one has been appointed, may, on behalf of the ward, resign with the approval in writing of the persons authorized by the instrument to appoint a new trustee in case of a vacancy if the instrument contains such a provision, and, if not, then with the approval of a court having jurisdiction to appoint a new trustee in case of vacancy.