Sorry, but no, you cannot sue the IRS.
Behar Intl. Counsel 619.234.5962 Kindly be advised that the answer above is only general in nature cannot be construed as legal advice, given that not enough facts are known. It is your responsibility to retain a lawyer to analyze the facts specific to your particular situation in order to give you specific advice. Specific answers will require cognizance of all pertinent facts about your case. Any answers offered on Avvo are of a general nature only, and are not meant to create an attorney-client relationship.
No you cannot sue the IRS and if you could you could not sue for "emotional distress".
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Your girlfriend's daughter is not technically your stepchild and therefore not a "qualified" child for the dependency exemption -- the reason is because you and she are not married. If you were then the child would be your "legal" stepchild for tax purposes.
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