In regard to adjudicating US Citizenship based on birth out of wedlock to a US Citizen father, you must have "legitimation" (legalizing the status of an illegitimate child) or, in lieu of legitimation, an acknowledgement of paternity in writing and under oath by the father or establishment of paternity by adjudication of a competent court in either Poland or the US prior to your child having reached the age of 18. [Ref. New Section 309(a) of the INA].
Answered on May 16th, 2012 at 12:51 PM