I dealt with this same situation last year and we were able to stop the counseling before it began. She probably is in contempt for (1) not giving you notice and (2) taking them to counseling without your permission. Find a local family law attorney and discuss this matter with them. Don't wait or things will only get worse.
She must share this info with you and given you have joint legal unless there is a provision which gives her more authority overy medical etc she could be in contempt.
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It is highly unlikely that there is a court order prohibiting the mother from taking the child to a therapist unless the father consents. However, if there is such an order, she is in contempt. Given the fact that I highly doubt that there is such an order, the question is best answered with an explanation of "joint custody". This means that each parent possesses the authority to make parental decisions for the child, which are typically medical care, religious training, schools, etc. It DOES NOT mean that each parent must agree before any medical treatment, etc. The one exception is schooling. In a 50/50 placement order, the parents must agree on where the child will go to school. If the therapy truly is absurd, and if it is not covered by insurance, you are better off attacking this problem from the perspective that you should not be required to pay half of the unnecessary and uninsured therapy expense.
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