Mo. Rev. Stat. § 454.1638: Effect of registration for enforcement.

(a) A support order or income withholding order issued in another state or a foreign support order is registered when the order is filed in the registering tribunal of this state.

(b) A registered support order issued in another state or a foreign country is enforceable in the same manner and is subject to the same procedures as an order issued by a tribunal of this state.

(c) Except as otherwise provided in sections 454.1500 to 454.1728, a tribunal of this state shall recognize and enforce, but may not modify, a registered support order if the issuing tribunal had jurisdiction.