A change to your custody agreement is possible. It can be a challenge. The court cannot consider a change of custody to be beneficial, as it can force the child to move and accept an unknown routine. Generally, the court will file an application for amendment when the amendment is in the best interests of the child and a substantial change in circumstances has triggered the application. The first is where the life of the non-killer parent has improved, but this has had little influence on how children are in the custody of the custodial parent. Remember that change focuses on the well-being of children. For example, a parent who has achieved long-term sobriety cannot really be a supporting factor in changing custody if, on the other hand, the children thrive in the custody of the other parent. .