You must be mistaken - IRS does not collect child support, state agencies do. If your income is not enough for affidavit of support purposes, you have to file it, anyway, but need someone to become a joint sponsor. Any person who is a U.S. citizen or a lawful permanent resident can become a joint sponsor on your wife's case by filing a second affidavit of support; all that person needs is income that exceeds the guidelines.
Answered on Aug 24th, 2012 at 2:57 PM