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I have been raising my daughter since she was 3-months-old. I am not her biological parent. She had minimal contact with her birth parents. She is informally adopted to me. I had power of attorney to be able to make all decisions needed. They had insurance through their jobs for her until she was 3 or 4. She has not had contact with them nor have they ever supported her in any way except for the few years of insurance. She is now 19 and in college. She went to file her taxes this year through TurboTax, and her taxes were rejected because someone else had used her SSN as a dependent. I have never claimed her because legally she wasn’t my child. She was told to either change her return so that someone was able to claim her or mail in the one that was done with a cover letter. I imagine the cover letter is to explain that she’s not lived with them etc. Can they still claim her when she hasn’t lived with them in 19 years and they don’t support her? We are going to do the cover letter and send it in as is.
Your daughter should follow the advice she received and if she still has questions, contact the IRS question line at (800) 829-1040. She will likely have to provide proof that she is qualified to file as an non-dependent. Since she has not lived in her biological parent’s household or received financial support from them everything should likely work itself out (hopefully).