(a) In applying the child support guidelines for an obligor who has children in more than one household, the court shall apply the percentage guidelines in this subchapter by making the following computation:
(1) determine the amount of child support that would be ordered if all children whom the obligor has the legal duty to support lived in one household by applying the schedule in this subchapter;
(2) compute a child support credit for the obligor’s children who are not before the court by dividing the amount determined under Subdivision (1) by the total number of children whom the obligor is obligated to support and multiplying that number by the number of the obligor’s children who are not before the court;
(3) determine the adjusted net resources of the obligor by subtracting the child support credit computed under Subdivision (2) from the net resources of the obligor; and
(4) determine the child support amount for the children before the court by applying the percentage guidelines for one household for the number of children of the obligor before the court to the obligor’s adjusted net resources.
(b) For the purpose of determining a child support credit, the total number of an obligor’s children includes the children before the court for the establishment or modification of a support order and any other children, including children residing with the obligor, whom the obligor has the legal duty of support.
(c) The child support credit with respect to children for whom the obligor is obligated by an order to pay support is computed, regardless of whether the obligor is delinquent in child support payments, without regard to the amount of the order.