So what finally got Robert Pattinson to move back in with Twilight costar and real-life love Kristen Stewart? Her passwords. Kristen had been trying to convince Rob that she never actually slept with director Rupert Sanders—just "engaged in several make-out sessions," as one source puts it to Radar—but Rob was wary. Until Kristen gave him all her voicemail and e-mail passwords, the source explains, "to prove she has nothing to hide and will do anything to get his trust back." Apparently Rob has never heard of the "delete" button.
Kristen certainly seems to be happier of late: Celebuzz reports that she was "all smiles" at yesterday's Balenciaga fashion show in Paris, and that even her hair and make-up looked "lighter" than usual. She was also wearing a sunny, feminine ensemble, as opposed to the darker, more casual look she usually sports. Perez Hilton adds that she even joked about her recent troubles at the event, telling Women's Wear Daily when asked about Paris' gray skies, "Yeah, I guess I’m used to it." But her newfound happiness may not last: "Kristen and Rob's friends absolutely don't believe" they'll actually stay together, a source tells Radar. "Rob's pals think it was easier for him to get back together with her right now because of the upcoming publicity blitz they are going to embark on to promote Breaking Dawn." (Read more Kristen Stewart stories.)