Section 5. (a) Unless otherwise directed by an instrument designating a custodial trustee pursuant to section three, a person, including a fiduciary other than a custodial trustee, who holds property of, or owes a debt to, an incapacitated individual not having a conservator may make a transfer to an adult member of the beneficiary’s family or to a trust company as custodial trustee for the use and benefit of the incapacitated individual. If the value of the property or the debt exceeds twenty thousand dollars, the transfer shall not be effective unless authorized by the court.

(b) A written acknowledgement of delivery, signed by a custodial trustee, is a sufficient receipt and discharge for property transferred to the custodial trustee pursuant to this section.