39 CFR § 762.30
Disbursement postal money orders issued to incompetent payees
November 6, 2020
(a) If the Disbursement Postal Money Order is endorsed by a legal guardian or other fiduciary and presented for payment by a bank it will be paid by the Postal Service without submission to the Postal Service of documentary proof of authority of the guardian or other fiduciary.
(b) If a guardian has not been or will not be appointed, the Disbursement Postal Money Order shall be forwarded to the Money Order Division, Postal Data Center, P.O. Box 14963, St. Louis, MO 63182, with a full explanation of the circumstances.