Cassadee Pope was proud to rock the new St. Jude This Shirt Saves Lives T-shirt on Monday night during a multi-artist variety show at Nashville's Schermerhorn Symphony Center. It's the least she can do for a hospital that has made an impact on her life.

Before the show, the "One More Red Light" singer looked back on her five years working with St. Jude. A record label representative urged her to tour the hospital in 2014, which put her way outside her comfort zone, even if she had done some similar things as a part of the rock band Hey Monday.

"I was actually nervous about how I would handle the situation, if I would break down," she shared, "And I actually went to it with a mindset of 'I need to be strong because I'm not the one going through this.'"

Like so many artists, what she found was a place of healing and joy. St. Jude Children's Research Hospital is world renowned for its advancements in fighting life-threatening illnesses like cancer, but it's also known for being a happy place in spite of the serious reason kids are there. She did arts and crafts and joked with patients. Pope says when you spend days worrying about ticket sales, radio airplay and promotional opportunities, something like this really puts it all into perspective.

"The thing that I took away from it was just how hopeful the kids were and they were happy and enjoying their time," the 29-year-old says. She would go on to play her new single "One More Red Light" and her country debut "Wasting All These Tears."

John Rich, Brett Young, LoCash, a Thousand Horses and RaeLynn also performed, while magician Justin Flom entertained after a unique fashion show that found all the models dressing up the same black This Shirt Saves Lives T-shirt. The night was the kickoff for the second-straight This Shirt Saves Lives campaign, which urges people to become St. Jude Partners in Hope. In fact, that's the only way to get the shirt. More than 70,000 people clamored for a gray version in 2017 and 2018.

Taste of Country and Townsquare Media have done an annual radiothon / webathon each year since 2014, raising close to $7 million. Each year more than 200 radio stations across America participate in Country Cares, a longstanding commitment to St. Jude from the country music community.

See More Photos from the This Shirt Saves Lives Concert