If she only made a small amount of income then they were not "wrong" in not withholding tax, but since she really had other income, it would have been better if she had completed a W-4 requesting that they withhold tax. ALL of the income the two of you had must go on your joint return. The untaxed income does affect your tax liability.
Every W-2 that you received must be reported on your tax return, even if they are for small amounts. Remember that each one of those W-2’s has your Social Security number on it, and that income was reported to the IRS by the employer. You do not want to get in trouble with the IRS for under-reporting your income.
ALL of your W-2’s must be entered on the SAME tax return. After you enter the first one, you click Add Another W-2.
**Disclaimer: Every effort has been made to offer the most correct information possible. The poster disclaims any legal responsibility for the accuracy of the information that is contained in this post.**
