The court will assume that four years of retroactive payments are in the best interest of the child. The court can order retroactive child support to be paid for the four years leading up to the date the support case was filed. childsupport.support Only the court can modify the order; it cannot be changed by agreement of the parties. However, it is possible that the judge could stray from the guidelines if using them would be unfair or inappropriate in a particular case.2 Parents will also be re...