Thank you for your patience as I am not the fastest of typers.
I can confirm that as you hold parental responsibility for your son then your ex is simply not able to take your son out of the Jurisdiciton to live elsewhere without your permission or in the absence of your permission, a court order allowing her to do so.
If your ex was to take your son, without your permission, or without a court order, then to do so could be investigated by the police as child abduction and if found guilty could lead to a jail sentence.
If you do not want to provide your permission for your son to live in America, then you do not have too. Your ex would then have to try to seek a court order to be able to do this and the current case law is that this is not an easy application for your ex to persaude the court.
The court would make a decision on whether such a move was in your son's best interests. The court would give high regard to your relationship with your son and how this relationship would be promoted. Your ex would have to convince the court that she could promote the relationship and give detailed plans to the court as to how she would do this. The court might also be concerned that the new partners job might simply lead to another move in the future and the court will want to be convinced of stability for your son for the future.
If you think that your ex is simply planning to go to court without your permission and this move is imminent then you can apply to your local family court for a Prohibited Steps Order to prevent her from doing so. You would do this by completing Form C100. The current court fee is £215 although you may get a reduction /waiver depending on your circumstances.
If the move is not imminent then you might want to consider mediation. This is actually a prerequisite before you can apply to court unless the matter requires the courts urgent attention (as per the above paragraph). Mediation might be able to help you to both agree, but if it doesnt then the court will have to make the decision.
Let me know if I can help you further
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