Comedy Central will air the “Night of Too Many Stars” this weekend, to benefit autism. “Daily Show” host Jon Stewart put the event together a few years ago to help his friend Robert Smigel, whose son has autism. Tina Fey, Seth Rogen, Amy Poehler, Stephen Colbert, Louis CK, Carly Rae Jepsen, and Sting all performed at the event, which airs at 7pm this Sunday on Comedy Central.

The benefit was taped last weekend, and tons of stars turned out, including Katy Perry. She performed with Jodi DiPiazza, who has a pretty inspirational story. Jodi was diagnosed with autism just before turning 2-years-old. Doctors told her parents that she may never be able to speak to them. But through music therapy, she started showing signs of progress. She is now studying piano and voice and New York’s Mannes College of Music Prep.

While Katy sang her hit “Firework”, Jodi sang along and accompanied her on piano.

Following the performance, Katy Tweeted, “I will never forget last night. It was the most important moment thus far of what I do.”

She followed with, “Jodi is my firework.”

Watch their performance here: