Miss. Code § 93-5-15
From and after March 15, 1934, any marital contract previously or hereafter solemnized by and under which parties have been duly and legally married, and one (1) of the parties to the marriage contract has become or becomes mentally ill to such an extent that it is necessary for a guardian to be appointed for that party, and the other party to the marital contract has committed any act that constitutes ground for divorce under the present laws, the guardian for the party with mental illness to the contract of marriage shall have the right to file a bill as the guardian, in the name of his ward, for the dissolution of the marriage, in the same way and manner and at the same place and on the same process that the person with mental illness could have done, if he had not become mentally ill.
Miss. Code § 93-5-15