California Code, Financial Code - FIN § 6752

(a) In the case of a minor, the receipt, acquittance, pledge, or other action required by the association or federal association to be taken by the minor shall be binding upon the minor with like effect as if the minor were of full age and legal capacity.

(b) Except under subdivision (c), the parent or guardian of the minor shall not have the power to attach or transfer any savings account issued to or in the name of the minor, provided that a parent or guardian of a minor aged 13 or less may require, by written notice delivered to the office where the account is maintained, that the signatures of both the minor and the parent or guardian be required for withdrawals from the account.

(c) In the event of the death of a minor the receipt or acquittance of either parent, guardian, or foster parent of the minor is a sufficient discharge of the association or federal association for any sums not exceeding in the aggregate two thousand five hundred dollars ($2,500) unless the minor has given written notice to the association or federal association to accept the signature of the parent, guardian or foster parent to withdraw a greater amount.