You need to file a modification to remove the residency restriction. You need a tough, smart attorney to help. You need to be able to prove that ex only saw the kids "every few months" for the past couple of years to help get the residency restriction lifted.
It appears that you live in Harris County so this website has plenty of great attorneys for you to choose from. Just look around - ignore the rating system - plenty of good attorneys have not "claimed" their listing. You might look under divorce, family, child custody, etc. to get a variety of attorneys. Most offer a free consultation in person or over the phone. Most offer payment plans to make their services affordable.
I only mediate these days -- hopefully, mediation is an option. It is normally more creative than going before the judge & also cheaper.
Fran Brochstein has over 20 years legal experience & enjoys educating the public about Texas laws. She is a full-time family law mediator in the Houston area. If you found this answer "helpful" or "best answer", please select the button to show your appreciation. Please understand that this is not a personal consultation and in no way creates an attorney-client relationship. You are strongly encouraged to consult with an attorney in your county in person about your specific legal problem. You can contact her at 713-805-9591 - 7 days a week - her personal cell phone.
Ms. Brochstein is correct. You need to file a motion to modify the parent-child relationship and ask the judge to lift the geographic restriction. And you really ought to hire a lawyer to help you do this. That geographic restriction is one of the more difficult things to get changed - a lawyer will be able to tell you how receptive your particular judge might be to this request, and help you get the evidence you need in front of the judge.
The answers you have received so far are excellent. This is not be easy. Get a good, very good lawyer.
Courts like both parents actively involved in their kids lives. Mom moving across the country makes that tough. His prior lack of involvement is huge.
File the modification ASAP. It can take a while and you should get started.
As the other attorneys have all correctly stated...get a family law attorney to assist you, as modification(s) of an order can be complex. It is worth the money you would spend to do so; and to know it has been handled correctly. Attempting to do it on your own can result in potential error(s) and more monies to correct it.
Rengin Bekhtyar's answer to a legal question on Avvo does not establish an attorney-client relationship.
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