You may be a United States citizen. There is not enough information to assess the matter. You can read more about the requirements at http://myattorneyusa.com/deriving-citizenship-through-parents-after-birth. In addition, you may be able to qualify for a fee waiver in order to request a replacement green card or to apply for naturalization. Read the instructions to Form I-912 found at www.uscis.gov.
Answered on Apr 21st, 2016 at 4:40 AM