Lady Gaga performed a moving tribute for her close friend, Sonja Durham, while performing at the 2017 Coachella Valley Music and Arts Festival on Saturday. Durham, who was once Gaga’s assistant, is battling stage IV breast cancer.

Before playing “Edge of Glory,” a single off of Gaga’s 2011 album Born This Way, the six-time Grammy winner dedicated the song to her Durham.

“My friend Sonja is very sick and I love her so much and if it’s okay with you, I’d like to sing this song for her,” Gaga said before breaking into an acoustic version of the song.

Halfway though, the thought of her friend became too much and Gaga had to pause for a moment.

“I’m sorry you don’t feel well. We all wish you were here with us,” Gaga said.

Durham documents her battle with cancer from her blog, “A ‘Lump’ in the Road.” It is she has referred to Gaga as her “guardian angel.”

“My guardian angel Gaga has stepped up in so many ways as well,” Durham wrote in a post from September 2016.

Gaga has also helped finance her treatment as well as Durham’s impromptu wedding to Andre Dubois.

“Honestly, if it wasn’t for Gaga and the financial contributions from everyone so far I really do not think I would be here,” she wrote in a post from April 14.

During the first weekend of Coachella, Gaga debuted a new song titled “The Cure.” She is currently touring promoting her album Joanne, released in October 2016.

Listen to the audio of “The Cure” below.

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