You must include your Spouse in your Will in Mississippi or the following law applies and the Spouse will take his or her share as provided for renounceation.

If the will of the husband or wife shall not make any provision for the other, the survivor of them shall have the right to share in the estate of the deceased husband or wife, as in case of unsatisfactory provision in the will of the husband or wife for the other of them. In such case a renunciation of the will shall not be necessary, but the rights of the survivor shall be as if the will had contained a provision that was unsatisfactory and it had been renounced. MS Code 91-5-27