In general, the courts tend to not require a stepparent to make child support payments for the child of their new spouse, from their prior relationship. Moreover, when the courts are initially calculating child support payment amounts, they will not even include the stepparent’s earnings as a factor. However, just like with any other matter that comes before the courts, there are always mitigating factors that they determine have a substantial enough impact, and are relevant enough, that it warrants being included in the decision making process, and the facts of a case may require the stepparents income to be included when deciding child support payments for the biological parent. For instance, if the support-receiving parent marries someone that reduces the cost of living for them, then a court may reduce the child support award to reflect an appropriate amount with respect to cost of living.
An exception to this would be if the stepparent decided to adopt the child, in which case they would be personally liable for child support. However, in order for this to occur, the parent of the child, who is not their current spouse, would normally have to terminate their parental rights in order for the stepparent to even begin the adoption process. In a regular scenario, however, stepparent are not required to pay child support for the spouse’s child.