Tex. R. Civ. P. 308a
When the court has ordered child support or possession of or access to a child and it is claimed that the order has been violated, the person claiming that a violation has occurred shall make this known to the court. The court may appoint a member of the bar to investigate the claim to determine whether there is reason to believe that the court order has been violated. If the attorney in good faith believes that the order has been violated, the attorney shall take the necessary action as provided under Chapter 14, Family Code. On a finding of a violation, the court may enforce its order as provided in Chapter 14, Family Code.
Except by order of the court, no fee shall be charged by or paid to the attorney representing the claimant. If the court determines that an attorney's fee should be paid, the fee shall be adjudged against the party who violated the court's order. The fee may be assessed as costs of court, or awarded by judgment, or both.
Tex. R. Civ. P. 308a