This question is for the Sisterhood of the Traveling Pants fans.?

Yes.

I thought they did.

I've found this on Wikipedia:

"The aftermath of Bridget's one-night stand with Eric differs significantly from the book. In the movie, he goes to Maryland to apologize to Bridget. In the book, it is left unclear as to whether Bridget has sex with Eric. In the third book it is established that they did in fact have sex the first summer. Bridget is hurt and falls into a state of depression evident in the second book. Eric and Bridget do not reconcile until the end of the third book."

Yeah, i asked myself the same thing. It didn't make sense cause it the first book, it didn't seem like it, but then she kept implying that shedid. She did sleep with him, it turns out, but the first book didn't really explain much.

No, but they do have a one-night stand.