Legal Question in Family Law in Texas

Did she take the children with her?

Nothing in court is "automatic." File your divorce petition, ask for custody, and see what happens.

There are no guarantees, and it depends on why she left in a secretive/abrupt manner. Was she afraid of the husband? Is she unstable? The number of reasons she left are infinite, and will bear greatly on the outcome. Husband can file a petition for divorce to bring the matter before the courts, and eventually resolve the issues of conservatorship and support.