(a) Except as provided by Subsection (b), the court shall order the termination of the parent-child relationship of a parent and a child if the court finds by clear and convincing evidence that:
(1) the parent has engaged in conduct that constitutes an offense under Section 21.02, 22.011, 22.021, or 25.02, Penal Code;
(2) as a direct result of the conduct described by Subdivision (1), the victim of the conduct became pregnant with the parent's child; and
(3) termination is in the best interest of the child.
(b) If, for the two years after the birth of the child, the parent was married to or cohabiting with the other parent of the child, the court may order the termination of the parent-child relationship of the parent and the child if the court finds that:
(1) the parent has been convicted of an offense committed under Section 21.02, 22.011, 22.021, or 25.02, Penal Code;
(2) as a direct result of the commission of the offense by the parent, the other parent became pregnant with the child; and
(3) termination is in the best interest of the child.