Legal Question in Family Law in New Hampshire

The technical answer to your question is 18. At that point the "child" becomes an adult. As a practical matter, in the course of a divorce, the input of the child is taken into consideration at all times. However, when a child is 12 or older, their input is generally given more weight. The court focuses on what is in the "best interest" of the child. Both parents are encouraged to have regular and continuing parental rights and responsibilities. In those cases where the parents can not agree on sharing those rights and responsibilities, the court will appoint a "guardian ad litem" to represent the interests of the child. This person conducts an investigation as to what is believed to be in the best interest of the child and offers a recommendation to the court as to what arrangement would be best for the child and the parents.

There is no "one size fits all" when it comes to parenting rights and responsibilities. I suggest that you need to meet with an attorney experienced in these areas who can offer more specific advice tailored to your personal family situation.