You should write a letter indicating that you no longer intend to be bound or to agree to the original terms. You should indicate that the original terms are not or no longer considered by you to be in the children's best interest. Although it is difficult to set aside an agreement, any agreement regarding children must be in the children's best interest. Additionally, courts are not bound by the parents' agreement when it comes to issues about children because the courts have a superseding interest in protecting the children of their own state.You should speak with an experienced attorney who is familiar with these areas of law.Good luck. Brad M. Micklin, Esq.187 Washington Ave., Suite 2FNutley, NJ 07110973-562-0100Brad@njdivorceattorney.net This information is based on New Jersey law and upon the limited facts you presented. My advice may be different if I find that the facts presented are different.  Additionally, this answer does not contain any confidential information nor does it create any attorney/client relationship.