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The Robin Hood Foundation’s 12-12-12 Concert for Hurricane Sandy Relief took place at New York’s Madison Square Garden last night! InStyle was backstage for the night’s biggest moments, where we spotted stars like Blake Lively (in Isabel Marant), Katie Holmes (in Tom Ford), and Jimmy Fallon with wife Nancy all strutting down the red carpet prior to their on-stage appearances. See more behind-the-scenes photos in the gallery!