Legal Question in Family Law in Virginia

No, the judge normally cannot modify the terms of such an agreement but can enforce its terms if necessary with the court's powers of contempt.

You can certainly ask the court to require your ex to comply with the terms of the agreement incorporated in the divorce decree. The judge would be unable to modify the spousal suport, since it was set by contract between the two of you. But the child support can be modified even though the agreement stated what it would be; the courts retain jurisdiction over the child and can change the support if it is found to be in the best interest of the child. It is unlikely a judge would permit him to seek to have the child support changed if he has not abided by the original order; he who would seek equity must have done equity. If the judge were willing to entertain a request to modify child support, In no event could the court modify the child support retroactively; the earliest it could only be effective would be the date of the petition to change child support.