I wish they would reveal these details in the show. Really, the woman got me thinkin'. I agree with Stella. I think Mac told Peyton about Claire (I really think so. She needed to know that 'cause well, they ARE having a relationship. It's vital to know those kind of things. Especially this is Mac we're talking about.) like he told Stella years ago (but somehow I also think that Stella mighta have known Claire for a while before 9/11).