I filed I-130 for my husband and it was recently approved when I was a LPR. Now I just became a citizen. We are still waiting for a visa. [indent][/indent]Should I file for a k3 visa or just send proof of my citizenship to the embassy in my husband's country?

Just found out that I was an American citizen since birth only last year through naturalized grandfather and father (both deceased now). Went to the US for the first time ever last Sept. to Oct. 2007 after living all my life in the Philippines. I need help as to what to apply for my kids. I am thinking of applying citizenship for them as children born abroad and file form N600k but I do not fulfill residency requirement of 5 yrs stay in the US but my father saw action in World War II in the Philippines which was an outlying possession at the time) Or do I file immigrants visa I-130 for them and my wife? My kids are 8 yrs old and 5 yrs old so they are aged-in regarding maximum ages and are considered immediate relatives not subject to visa quotas. I just want to make sure I file the right form so I don't waste time and money. The quickest way to get my family in the US is what I am looking for. I expect to go ahead of them first and settle in Houston, TX to establish residency and have a head start. Any ideas whether my case can be considered for N600k or I-130 is much appreciated. Thanks