Though neither made an appearance at Sunday's 54th Annual Grammy Awards, all eyes were on Britney Spears and Kim Kardashian the night before at Clive Davis' and the Recording Academy's 2012 Pre-Grammy gala and salute to industry icons honoring Richard Branson.

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Inside the Beverly Hilton Hotel, Spears, 30, turned heads in a plunging Herve Leger dress and YSL heels. The "Criminal" singer was joined by fiance Jason Trawick, who proposed in December. New single Kardashian, 31, wore a cleavage-enhancing Antonio Berardi gown.

"Kim and Britney met a few times before," a source close to the E! reality star tells Us Weekly. "Kim has been to her concert a few times. Britney and Kim love each other."

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According to the source, the two stars chatted about "normal girlie things" during the star-studded event, which brought out celebs like Brandy, Tom Hanks, Michelle Trachtenberg, Gabrielle Union, Diana Ross, Ne-Yo, Kathy Griffin, Darren Criss, Ciara, Blake Shelton, Miranda Lambert and Monica.

Despite their happy reunion, "the mood of the party was sad" as guests learned of Whitney Houston's sudden passing. "Everyone was still in shock."

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Shortly before guests arrived, Houston, 48, was found lifeless in her hotel room's bathtub a few floors above the party. The "I Will Always Love You" singer is survived by her daughter Bobbi Kristina, 18, and her mother Cissy. Houston's death was reportedly caused by a lethal combination of prescription pills and alcohol; toxicology results are pending.

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