I once was at a party where a friend brought a friend from another city, and I for some reason had this strong feeling that I knew her despite also knowing for

I once was at a party where a friend brought a friend from another city, and I for some reason had this strong feeling that I knew her despite also knowing for certain that I'd never seen her before (I'm very good with remembering faces). Halfway through the evening, without us really talking before she suddenly asks me if we know each other somehow, because she feels like we've met before even though she's pretty confident that she hasn't. You can probably imagine how intriguing it was that both of us had the same experience! So obviously we have to know each other, right? But then as we try to figure out from where we might know each other, all we end up doing is firmly establishing that no, we really don't have any mutual friends or contacts or hobbies or anything that could connect us. But after reading this comment and the responses to it I'm now realizing the city that she came from did happen to be the one where me and my parents lived for half a year when I was four, so maybe we went to the same kindergarten and were close friends at the time?