Wearing a red sleeveless gown with a striped sequin nude illusion bodice and thigh-high slit from Georges Chakra, she dazzled on the red carpet while holding a pink clutch purse.
Lambert also wore a pin with a gold number 1 on it, in tribute to the victims of the mass shooting at the Route 91 Harvest Festival last October, in which 851 country fans were injured and 58 were killed. The shooting, the largest mass shooting in American history, occurred during Jason Aldean's headlining set at the festival.
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"A lot of them were there that weekend playing on that same festival," he told ET. "So I think for me to go back in this way, with all those people, is kind of the perfect way to really go back and do it for the first time."