Ariana Grande's vocal chords got quite the workout on Sunday (June 4), when she belted out song after song at One Love Manchester. She organized the benefit concert to honor and support victims of the terrifying attack at her Manchester Arena show last month — especially the 22 individuals who died and the scores more injured that night.

Olivia Campbell, 15, was one of those people. In between performances, Ari opened up about meeting Olivia's mom following the tragedy.

"I had the pleasure of meeting Olivia's mommy a few days ago and as soon as I met her I started crying," Ari told the crowd of 50,000 fans at Emirates Old Trafford Cricket Ground, a few short miles from Manchester Arena. Miley Cyrus, Katy Perry, Justin Bieber, and more of your favorite artists came out for their own performances.

"I gave her a big hug and she said [to] stop crying because Olivia wouldn't have wanted me to cry. Then she told me that Olivia would have wanted to hear the hits. So that being said, we had a totally different show planned. We had a rehearsal yesterday and we changed everything."

And that, my friends, is how Ari ended up singing "Side to Side," her risqué collab with Nicki Minaj.

"I think that the kind of love and unity that we are displaying is the medicine that the world really needs right now," Ari said. "This evening has been so light and so filled with fun and love and bright energy, and I want to thank you for that."

Check out the highlights from One Love Manchester:

For additional reporting on the Manchester attack, how you can help, and more, click here.