It was a much different kind of performance for Taylor Swift at Friday's star-studded Stand Up to Cancer benefit at the Shrine Auditorium in Los Angeles.

One day after her sexy, crowd-diving rendition of "We Are Never Ever Getting Back Together" at the MTV Video Music Awards, the 22-year-old singer brought the audience -- and herself -- to tears debuting her new song "Ronan."

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Wearing a girly red dress, a teary-eyed Swift crooned the moving, acoustic ballad, dedicated to the late Ronan Thompson, a 3-year-old boy who died of neuroblastoma in 2012. (Ronan's mother Maya co-wrote the song, whose proceeds will go to cancer research.) After the performance, the Grammy winner was seen wiping her eyes as she walked offstage.

Among the other attendees for the fundraiser, which was broadcast on all four major networks, was surprise guest Robert Pattinson; Kristen Stewart's estranged beau appeared poised and serene speaking onstage for the cause.

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Presenting a video presentation, Justin Timberlake (whose fiancee Jessica Biel was also on hand) was similarly emotional.

Others on hand included Alicia Keys, Gwyneth Paltrow, Jennie Garth, Halle Berry, Minka Kelly, Julia Roberts, Tom Hanks, Samuel L. Jackson, Stacy Keibler, Gabby Douglas, Sofia Vergara, Seth Rogen and Katie Couric.

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The night also served as a tribute to legendary movie and TV producer Laura Ziskin, who died of breast cancer in June 2011.

This article originally appeared on Taylor Swift Cries at Emotional Stand Up to Cancer Performance