Mila Kunis, Ashton KutcherMila Kunis, Ashton KutcherRyan Reynolds, Blake LivelyAdam Brody, Leighton Meester

With the news of Adam Brody and Leighton Meester's engagement, our present day selves immediately reverted back to our teenage star-struck selves, when the soundtrack to our lives was "California here We Come" and we couldn't wait to see who Gossip Girl spotted that week. In this ultimate crossover event, that Josh Schwartz couldn't even have conjured up, our favorite fictional characters - Seth Cohen and Blair Waldorf - have turned into a real-life romance. In honor of the best celeb couple news of the year, check out our favorite on-screen characters that fell in love in real life.