The UTMA is one of many 'uniform' laws that may be adopted by each state. If I recall all 50 states have adopted the UTMA. The state law that probably will apply is the state in which the account was established; however, for my organization all are treated in accordance with VA law. Also, each state may incorporate its own variations; such as with the UCC.
If the account was a UTMA, the transfer was an irrevocable transfer to you the minor. The money was/is yours. In VA a minor has a right to demand an accounting of the funds, generally this has to be accomplished through the court.