Mont. Code Ann. § 32-2-917

Whenever a deposit is made in a mutual association by or in the name of a minor, the deposit must be held for the exclusive right and benefit of the minor and free from the control or lien of all other persons, except creditors, and must be paid, with any interest due, to the person in whose name the deposit was made. The receipt of the minor is a sufficient release or discharge for the deposit to the mutual association.