Custody orders come from a judge and are like any other court order. If the other parent in your situation refuses to abide by the order, you have the right to let the court know and ask for actions to force that person to comply.
Texas Law Help explains the courts want parents to work together to raise their children and will hold parents responsible for being in contempt of a custody order.
First steps
Once the other parent shows you he or she will not follow the court custody order, you should try to resolve the issue outside of court. You can go through mediation or talk through the issues. If this fails, then you will need to put together a petition.
Failure explanation
The petition will need to explain exactly how the other parent failed to follow the order. You will want to have evidence to back up your claims, such as video, text messages and witnesses. You also must give very specific details, including dates and times of when the other parent broke the terms of the custody order.
Do note that if your court order does not give specific details on parenting time, it may be difficult to enforce a contempt claim. You cannot simply say the other parent refuses to let you see your children. You must point out how the order says you get the children at specific times and days and then show the other parent did not abide by those orders.
Pattern of behavior evidence
You also need to make sure you show the contempt actions happen repeatedly. You cannot make a claim after one time of the other parent denying you parenting time. There has to be an ongoing issue at hand.
Proving the other parent has broken the court order can be tricky, but if you have hardcore evidence on your side, you may be able to get help from the court.