Your question is a difficult one to answer as there are so many factors to consider.
Your income makes you able to care for your children, but it also makes you able to pay her more in child support.
The fact that she is living in her stepfather's trailer and it is filthy should help you, but it is not dispositive. Furthermore, if she gets temporary support, she can use it to move to a better place.
Is she working? Are the children currently with her? Does the stepfather have a criminal record?
These are all issues you should discuss with your attorney, who should be an experienced family law practitioner in Harris County.
Don't wait, however, in the hope that you can convince her to return. You need to 'lawyer up' and start the process now, before the children are endangered by their mother's living situation.
The information you have provided is helpful, but not dispositive. I would be more interested in knowing, where the children currently reside, who cares for the children on a daily basis, who prepares their meals, prepares them for bed, takes them to school, church, doctors? These facts are more the basis of a custody decision. Go talk to an attorney and they can get the relevant information from you to give you a better idea of where you stand.
Do you have a family law attorney representing you yet? If not, hire one immediately. You need temporary orders in place providing for the temporary custody and visitation of the children while divorce is pending. You need a game plan to provide care for the children while you work should the court grant you temporary custody. if you obtain temporary custody of the kids, she would have some type visitation. Assuming that works out and the kids do fine on the temporary basis, you could then argue why should circumstances change at final orders. It is NOT impossible for a dad to have primary custody. The controlling issue is the "best interest" of the children. Find a family law specialist.
I am not intending this to be legal advice, because I don't know the particulars of your situation. Call me if you would like to discuss this or other isues.
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