§ 155.201. Mandatory Transfer
(a) On the filing of a motion showing that a suit for dissolution of the marriage of the child's parents has been filed in another court and requesting a transfer to that court, the court having continuing, exclusive jurisdiction of a suit affecting the parent-child relationship shall, within the time required by Section 155.204, transfer the proceedings to the court in which the dissolution of the marriage is pending. The motion must comply with the requirements of Section 155.204(a).
(b) If a suit to modify or a motion to enforce an order is filed in the court having continuing, exclusive jurisdiction of a suit, on the timely motion of a party the court shall, within the time required by Section 155. 204, transfer the proceeding to another county in this state if the child has resided in the other county for six months or longer.
(c) If a suit to modify or a motion to enforce an order is pending at the time a subsequent suit to modify or motion to enforce is filed, the court may transfer the proceeding as provided by Subsection (b) only if the court could have transferred the proceeding at the time the first motion or suit was filed.