Mo. Rev. Stat. § 474.140: Inheritance and statutory rights barred on misconduct of spouse.

If any married person voluntarily leaves his or her spouse and goes away and continues with an adulterer or abandons his or her spouse without reasonable cause and continues to live separate and apart from his or her spouse for one whole year next preceding his or her death, or dwells with another in a state of adultery continuously, such spouse is forever barred from his or her inheritance rights, homestead allowance, exempt property or any statutory allowances from the estate of his or her spouse unless such spouse is voluntarily reconciled to him or her and resumes cohabitation with him or her.