Tex. Penal Code § 25.03

(a) A person commits an offense if the person takes or retains a child younger than 18 years of age:

(1) when the person knows that the person's taking or retention violates the express terms of a judgment or order, including a temporary order, of a court disposing of the child's custody;

(2) when the person has not been awarded custody of the child by a court of competent jurisdiction, knows that a suit for divorce or a civil suit or application for habeas corpus to dispose of the child's custody has been filed, and takes the child out of the geographic area of the counties composing the judicial district if the court is a district court or the county if the court is a statutory county court, without the permission of the court and with the intent to deprive the court of authority over the child; or

(3) outside of the United States with the intent to deprive a person entitled to possession of or access to the child of that possession or access and without the permission of that person.

(b) A noncustodial parent commits an offense if, with the intent to interfere with the lawful custody of a child younger than 18 years, the noncustodial parent knowingly entices or persuades the child to leave the custody of the custodial parent, guardian, or person standing in the stead of the custodial parent or guardian of the child.

(c) It is a defense to prosecution under Subsection (a)(2) that the actor returned the child to the geographic area of the counties composing the judicial district if the court is a district court or the county if the court is a statutory county court, within three days after the date of the commission of the offense.

(c-1) It is an affirmative defense to prosecution under Subsection (a)(3) that:

(1) the taking or retention of the child was pursuant to a valid order providing for possession of or access to the child; or

(2) notwithstanding any violation of a valid order providing for possession of or access to the child, the actor's retention of the child was due only to circumstances beyond the actor's control and the actor promptly provided notice or made reasonable attempts to provide notice of those circumstances to the other person entitled to possession of or access to the child.

(c-2) Subsection (a)(3) does not apply if, at the time of the offense, the person taking or retaining the child:

(1) was entitled to possession of or access to the child; and

(2) was fleeing the commission or attempted commission of family violence, as defined by Section 71.004, Family Code, against the child or the person.

(d) An offense under this section is a state jail felony.

(e) If conduct that constitutes an offense under Subsection (a)(3) also constitutes an offense under Section 20.03, the actor may be prosecuted only under Section 20.03.