Legal Question in Family Law in Texas

Unless the two of you have some kind of court order in place regarding custody, neither one of you has any more right to the kids than the other one does. That's just for informational purposes, and I want to make it clear that I'm not advising you as to what you should do. One option that might strengthen your position a bit (though admittedly it's VERY last minute at this point), would be to file what's called a SAPCR case ("Suit Affecting Parent-Child Relationship"), asking for custody of the kids, child support, etc., and make sure both that he knows about it before he leaves and that he is aware that it is a felony offense to leave the state with the intention of permanently removing a child from the court's jurisdiction if you are aware that a SAPCR had been filed--even if there are not temporary orders in place yet. Realistically, if he's leaving Friday, you'd have to do all of this tomorrow (get the SAPCR petition filed and give him a copy with witnesses who'd be able to confirm delivery), so I don't know how feasible that's going to be for you, practically speaking. Maybe you can get lucky and find an attorney who can take care of the initial filing and notice very quickly tomorrow, and then again, maybe not. Good luck.