Your question is a bit difficult to decipher. That being said, child support isn't based on demonstrated need, it is established using a statutory guideline that takes into account certain relevant factors such as your income, the other parent's income, your respective timeshare with the children, your insurance costs, hardships, your tax deductions etc... It does not take into account your actual monthly expenses.
The court won't just let arrears accrue if he genuinely has no income and there isn't a reason for the court to impute income to him - such as he is willfully unemployed. If he already owes you money for past support, there are steps you can take to levy his accounts or property to collect on that debt - but you will likely require an attorney's assistance. I would encourage you to meet with an attorney in your area to discuss the specific facts of your case and see what alternatives may be available to you.
Best of luck.
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