SDCL § 25-7-6.23: Offset of support obligation when each parent has primary physical custody of at least one child--Computation--Assistance from department.

If the parents have two or more children between them and each parent has primary physical custody of at least one child, the child support obligation shall be determined by computing the amount of each parent's respective support obligation for the children in the other parent's physical custody, and the support obligations shall be offset in determining a monthly support obligation. If one or more of the children are receiving assistance from the department as provided in § 28-7A-7, and in lieu of the offset, each parent shall be obligated to pay the respective support obligation amount to the other parent.