Assuming this is a genuine marriage, I suggest you appear at the interview alone, have a letter from the treating physician confirming your wife's condition and ask the USCIS officer to reschedule the interview to a later date. Chances are USCIS will agree and send you another interview date for 1-2 months after your original interview date.
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.
Prove your wife's condition and ask to reschedule
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Reschedule the interview with evidence of her hospitalization.
J Charles Ferrari Eng & Nishimura 213.622.2255 The statement above is general in nature and does not constitute legal advice, as not all the facts are known. You should retain an attorney to review all the facts specific to your case in order to receive advise specific to your case. The statement above does not create an attorney/client relationship. Answers on Avvo can only be general ones, as specific answers would require knowledge of all the facts. As such, they may or may not apply to the question.