While we can't imagine anyone other than Blake Lively and Leighton Meester playing the roles of Serena and Blair on ‘Gossip Girl’, casting director David Rapport has revealed that the two actress’ weren't the studio’s first choice. Instead Rumer Willis and Ashley Olsen were the studio's top picks to play the Upper East Side queens.

Rumer WillisRumer Willis was almost cast in ‘Gossip Girl’.

"I think the network initially pitched us Ashley Olsen and Rumer Willis for Blair and Serena,” Rapport told Buzzfeed. "I love Rumer, she’s grown into quite an amazing actress and person, but that, to me, was based on protecting the investment of a television show where creatively, these lesser-known girls really captured the essence of the show and carried it for six years.”

According to Rapport, the network had to be convinced that California-girl Blake would be able to pull off playing a girl from New York’s Upper East Side. “Blake was the front-runner. We did a screen test with her and the note we got back was that she was ‘sunny California’ and they said, ‘I don’t think we’ll buy her as an Upper East Side debutante.,” Rapport revealed.

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"So we did another screen test with Blake and all we did was straighten her hair to make her look a little more sophisticated, so to speak. What’s ironic is, in the pilot, she ends up having the wavy hair.”

“From there on out, so much of the casting on 'Gossip Girl' became about the hair because Leighton Meester is naturally blonde and the way we got her the job was we dyed her hair,” he added. "Ultimately they were the best actors for it and brought something really special to their roles.”

As for what made Leighton stand out from the pack, it was the fact that she didn't seem too bothered as to wether or not she landed the role. “Leighton is a little bit colder than Blake but I like that,” Rapport said.

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"Leighton wasn’t a bitch when she came in, but she wasn’t overly nice or overly generous. She was professional and she did the job and played the role well, and what I liked about her is that she owned who she was. She wasn’t going to kiss everyone’s ass and that was very Blair.”

‘Gossip Girl’ ran on the CW network for six seasons, before bowing out in 2012. But although Blake and Leighton were undoubtedly the best choices for the roles, Rapport sure has given us something to think about. Can you actually imagine a ‘Gossip Girl’ with Ashley Olsen and Rummer Willis?