If a child support order issued by a tribunal of this state is modified by a tribunal of another state that assumed jurisdiction under the Uniform Interstate Family Support Act, a tribunal of this state:
(1) may enforce the order that was modified only as to arrears and interest accruing before the modification;
(2) may provide appropriate relief for violations of the order that occurred before the effective date of the modification; and
(3) shall recognize the modifying order of the other state, on registration, for the purpose of enforcement.
Official text of the Texas Family Code as published by the Texas Legislative Council.