Mo. Rev. Stat. § 452.860: Enforcement of registered determination.

1. A court of this state may grant any relief normally available under the provisions of the laws of this state to enforce a registered child custody determination made by a court of another state.

2. A court of this state shall recognize and enforce, but shall not modify, except in accordance with sections 452.740 to 452.845, a registered child custody determination of another state.