If your sister does not have the W-2's and any other income documents, she will need to visit her local IRS office to get a Transcript for each of the past three years. (2007,2008, and 2009). These are the years that are still open for getting a refund. The Transcript will contain the information she needs to file the returns. Some IRS offices offer Taxpayer assistance with filing the returns. If there is not an office nearby, she can get the Transcripts by calling(NNN) NNN-NNNNor by filing form 4506-T.
The IRS will probably not require her to go back farther than this unless the returns are showing balances due. Hopefully, she has refunds coming.
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