Mississippi Code Title 81. Banks and Financial Institutions § 81-5-63

(2)(a) Any bank may pay to the successor of a deceased depositor, without necessity of administration, any sum to the credit of the decedent not exceeding Twelve Thousand Five Hundred Dollars ($12,500.00), without liability to any other persons, relatives or beneficiaries, and the receipt of acquittance of the person so paid shall be a valid and sufficient release and discharge to the bank for any payment so made. This section shall apply to all banking institutions, including national banks and postal savings banks within the state. The term “deposit” as used in this section shall include, but not be limited to, any form of deposit or account, such as a savings account, checking account, time deposit, demand deposit or certificate of deposit, whether negotiable, nonnegotiable or otherwise.

(b) For the purposes of this subsection, “successor” means the decedent's spouse; or, if there is no surviving spouse of the decedent, then the adult with whom any minor children of the decedent are residing; or, if there is no surviving spouse or minor children of the decedent, then any adult child of the decedent; or, if there is no surviving spouse or children of the decedent, then either parent of the decedent; or, if there is no surviving spouse, children or parent of the decedent, then any adult sibling of the decedent.