If you have a 50% say on non-emergent health care issues, and you have that in a written parenting plan, you may seek enforcement of the provisions of the parenting plan in court, however, you should look at the parenting plan first to see if the plan requies alternate methods of dispute resolution prior to seeking court intervention. However, a 50% say is not an ultimate say, as under the scenario you described, presumably your ex has a 50% say as well.
In issues involving a minor child, a court is going to look at what is in the best interests of the child, and the court may look at all legal and equitable factors in making a decision. It is important to ask yourself, prior to seeking any action against your ex, what is really in the best interests of your daughter.
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