Malkin was born, I believe, in Philly, in 1970. Because she was born to Filipino parents, she is technically a duel-citizen under Filipino law, explained here: http://www.philcongenla.org/content.asp?FileName=%5Cconsular%5Ccitizenship_faq.ini#3
Relevant quote: "Dual citizenship is the status of a person who is a citizen of two or more states. For example, a child born in the United States of parents who are Filipino citizens is both a Filipino (since his parents are Filipinos at the time of birth) and an American (since he was born in the United States)."
She would need to file an "Express Renunciation of Citizenship" to no longer be a duel-citizen, and as best as my research could gather, she hasn't.
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Oh, please. She's still an American. Your statement was misleading.