See the case In Re Marriage of Turk (Illinois Supreme Court 2014).father and child

The court ruled that the custodial parent can be made to pay the noncustodial parent to alleviate the noncustodial parent’s inability to pay their share of their responsibility to support the child.

“the final child support order may result in a “negative” payment to the custodial parent”

Thus resulting in child support payments to the noncustodial parent.