For the past few seasons, we've seen Elena grow feelings her boyfriend's brother, Damon. When she transitioned into a vampire, those feelings were magnified, and Stefan realized that their relationship had hit an obstacle they couldn't overcome. They broke up, and Elena ran straight into Damon's arms... and his bed. Delena fans were overcome with excitement, but intercut with scenes of hot vampire Delena sex was Caroline's crazy realization: maybe the reason Elena's been acting so different and into Damon is not because, you know, she just became a member of the growing Mystic Falls vampire community, but actually because Elena may be sired to Damon. Stelena fans rejoiced, and Delena fans weren't sure what to feel. VERDICT: We'll have to wait for next week's episode to find out if Caroline's theory is just a theory, or if there is some truth to it.