The most important building block to any great on-screen couple is chemistry, that certain intangible energy between two people that makes us, the viewer, get lost in the moment and wrapped up in their storyline. And while great actors can create that chemistry, sometimes it just comes naturally. Sometimes two actors not only hook-up on screen, but that chemistry carries over into their everyday life. Hell, sometimes, like in the case of True Blood's Anna Paquin and Stephen Moyer, it even leads to two stars exchanging wedding vows.

From Full House's John Stamos and Lori Loughlin to Revenge's Josh Bowman and Emily VanCamp, check out some of the greatest on-screen pairings that wound up turning into real life couples.

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