"Metspitzer" wrote
Expect your niece to get a W-2 with reported taxes withheld. They may gross up the pay to cover the taxes, that or just not have enough federal or state withholding. If the amount retained by the employer wasn't enough to cover the taxes that should be withheld then they may gross up her pay to cover the taxes "withheld" or that should have been withheld.
A lesson here is to know exactly how an employer intends to treat the worker before hiring on.