Legal Question in Family Law in Texas

Read your order. It probably has language concerning who has the right to make medical decisions.

Typically, each parent has the right to handle routine medical decisions. There are usually special rules for invasive medical procedures. I don't know where vaccinations fall, but if the latter, then it makes a difference. If you do it and she complains to the court, you will probably claim that this is a routine medical decision and she will claim that it is an invasive procedure. If the court decides that it is the former, then you are OK. If the court decides that it is the latter, then:

If it is both of you or just you, then you can do so. If it is either of you with the consent of the other, then both parents have to agree. If it is either of you with notice to the other parent, then you would have to tell her that you are doing it.

Note that the Attorney General's standard order is different. It typically gives both parents the right to make medical decisions in an emergency involving immediate danger to the child's health and safety and gives one parent the right to consent to medical treatment involving invasive procedures; it does not address routine medical decisions.