Former Arizona Rep. Gabrielle Giffords and her husband, Mark Kelly, at an April 16 ceremony naming a Capitol Hill conference room for her aide Gabe Zimmerman. Zimmerman died in the same Tucson, Ariz., shootings that Giffords wounded. Saul Loeb/AFP/Getty Images hide caption

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Former Rep. Gabby Giffords, D-Ariz., and her husband Mark Kelly at Wednesday's Senate hearing about gun violence. Chip Somodevilla/Getty Images hide caption

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Rep. Gabrielle Giffords last May. P.K. Weis/Facebook.com/GabrielleGiffords hide caption

itoggle caption P.K. Weis/Facebook.com/GabrielleGiffords

Taken on May 17, this photo of Rep. Gabrielle Giffords (left) and her mother, Gloria Giffords, was posted on her Facebook page on June 12. P.K. Weis/Facebook.com/GabrielleGiffords hide caption

itoggle caption P.K. Weis/Facebook.com/GabrielleGiffords

May 28, 2008, file photo: Space shuttle Discovery commander Mark Kelly, right, gestures as he walks with his twin brother astronaut Scott Kelly, left, and mission specialist Ron Garan, after arrival at Kennedy Space Center in Cape Canaveral, Fla. Terry Renna/AP hide caption

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