My wife's 2 daughters are coming to the US in June on an IR-2 Visa from the Philippines. The girls are 10 and 13 years old. My wife is a naturalized US citizen as of the beginning of 2009. Now if I understand it correct the girls will be automatic a US citizen when they enter the US so a few questions. 1) If I understand it correct we would need to file a N-600 we want to get a certificate of Citizen. Do we need to do this or is this optional. 2) If the statement above is correct and they are US citizen when they enter can we apply for a US passport immediately and what would we need to provide to prove that they are citizen. 3) I am planning on picking them up in the Philippines and bringing them back is they anything we need to do at immigration and should I expect any issues since I am not just the stepfather. I think that it for the moment I would appreciate any help you guys can provide.