Michigan Compiled Laws, Chapter 554. Real and Personal Property § 554.547

Sec. 27. (1) Transfer of custodial property to the minor that is transferred to the custodian under section 8 or 9  1 may be delayed as provided in this section until a specified time after the minor is 18 years of age. The time of transfer to the minor shall be specified in the transfer executed under section 13  2 by using the words “as custodian for (name of minor) until age __________ under the Michigan uniform transfers to minors act”.

(2) Transfer to the minor of custodial property transferred to the custodian under section 8 shall not be delayed later than the minor's twenty-first birthday. Transfer to the minor of custodial property transferred to the custodian under section 9 shall not be delayed unless the governing will or trust provides in substance that the custodianship continues until the minor is a specified age, not later than the minor's twenty-first birthday and that the will or trust determines the time to be specified in the transfer.