Yes, you both have equal right to the children. First, I would try and get an earlier Court date. Next, the best way for you to see them is to try an see them at public places like school or extracurricular activities. If she leaves them with friends or a relative, you may try to visit then as well. This is only a short-term solution.
She is enjoined from this type of behavior through the Denton County Standing Order (http://dentoncounty.com/dept/District_Clerk/Acrobat/DCSORCPCP.pdf). In order to be prepared for the Court hearing, be sure that you can document your repeated attempts to see the children. You need to be sending emails, texts, etc., and asking politely to see your children. If she continues to refuse, the Court can sanction her and give the children to you for additional periods of possession. You will need to file a Motion for Enforcement to enforce the standing order and set it at the same time as your Temporary Orders Hearing. Without this Motion being filed, the Court will not be able to punish her.
I would also consult an attorney. If she is refusing to allow you to see your children now, she will likely continue to do so until you hire strong counsel.
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