We should check the math of an offset calculation of child support. For example, in a situation where each parent has custody of two children of the marriage about 50% of the time, the court often looks at what child support one parent would pay for two kids based on that income, and what the other parent would pay for two kids on the other income. Then, you look at the difference, and the person who makes more money pays the difference. Sometimes it works out to be a wash, and no child support is ordered.