My husband and I separated for a few years and during that time he had a child. However, er got back together and now the child's mother has a child

In New York, biological parents are primarily responsible for supporting their children. As a stepmother, you are generally not obligated to pay child support for your husband's child from another relationship. However, if the biological parents' support is insufficient and the child is at risk of needing public assistance, the court may consider the step-parent's financial resources to ensure the child's needs are met. Given that your husband is unemployed, it's possible the court could look to your household income to support the child and prevent reliance on public assistance. It's advisable to consult with a family law attorney to understand your specific obligations and options in this situation.