Child support and special needs

How do the costs of a private special education for an other child (not of marriage) factor in to child support calculations for child of marriage? The other child is my sole financial responsibility.

According to the child support guidelines a parent’s financial responsibility for a child residing with you is equal to the basic child support obligation for that child based on your income, that amount is deducted from your income for purposes of calculating support for the other child.

The guidelines say: A parent’s financial responsibility for his or her natural or adopted children who currently reside with the parent (other than children for whom child support is being determined in the pending action) is (a) equal to the basic child support obligation for these children based on the parent’s income if the other parent of these children does not live with the parent and children; or (b) one-half of the basic child support obligation for these children based on the combined incomes of both of the parents of these children if the other parent of these children lives with the parent and children. If the other parent does not have income, the worksheets do not calculate the obligation correctly.

If the child for whom support is not sought has extraordinary expenses that would be considered in the prior child support obligation.

Surely a single parent would not be penalized. Am I wrong?

The guidelines to not provide for consideration of the extraordinary expenses.