Writing a letter of instruction can help expedite the estate planning process. If it is an emergency hearing, you must call. a.s.a.p. Arizona Rule of Family Law Procedure 49 (Rule 49) requires both parties to share information in family law cases. That might be your successor trustee. For those without a trust, it could be the personal representative of your estate. A letter of instruction is a document that lists all relevant financial information that your family members or executor need if something happens to you. We exist to provide permanently affordable housing for low to moderate-income individuals and families; promote community revitalization.