Children born in the state of New Jersey are to stay in this state absent a written agreement between the parties, or a court order. I'd recommend that you file a motion for custody and for removal from the state. As they are older children, the court will certainly hear from them and take their opinions into account, but until 18, a child has no "choice" as to where he or she will live. Either the parents decide together, or the court will decide.
The judge will decide. There is no magic age when children get to decide custody. The best interest of the child is the standard.
The law regarding a child's 'right'* to choose is a matter for each State and jurisdiction. The judge in most States, not the child, makes the decision based on the best interest of the child. Although not a standard by any means, many States have begun to give 'consideration' to a child's declaration of custodial preference when the child reaches the age of twelve or thirteen, sometimes fourteen. There are even cases when children of age 9 are allowed to testify.
The judge is normally given almost unlimited latitude in whether or not she or he listens to a child and how much weight to give to the child's wishes. In short, there is no specific "age" but the younger the child the less likely for a judge to give the stated preference much weight.
Good luck to you.
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