Is it lawful for a court to excuse an arrearage from past due child support to the date when the children respectfully reach the age of majority rather than the date of filing the petition to modify?

A hypothetical situation: Client made unsuccessful attempts to modify his child support obligation at the time each of the three children involved reached the age of majority. While a petition to modify the child support amounts should have been filed earlier, the law does not preclude the court from excusing the support arrearages that have recently accumulated. These arrearages only recently began to accumulate and all the arrearages are for children that have attained the age of majority. The language of the final judgment clearly indicates it was not the trial court’s intention, at that time, for respondent to still be paying support for the children.