Watch Kelsea Ballerini, Carrie Underwood and Keith Urban Sing Backstage at the Opry

Kelsea Ballerini was inducted into the Grand Ole Opry on Tuesday night, April 16, but one of her favorite moments likely happened off stage, prior to her induction. The Tennessee native shared a video of Carrie Underwood and Keith Urban joining Ballerini in singing Trisha Yearwood's 1992 classic hit, "Walkaway Joe."

"Sometimes the most unforgettable moments are the unplanned ones," Ballerini wrote. "Like this. Backstage at the Opry with two of my heroes singing one of my all time favorite songs. What a life."

Ballerini and Underwood later sang "Walkaway Joe" as a duet, after Underwood made Ballerini the newest member of the Grand Ole Opry.

"I want to thank [the Grand Ole Opry] for asking, this talented, incredible, smart, sweet, beautiful, woman to be a member," Underwood said from stage. "You have accomplished so much, in your career. And, you will undoubtedly accomplish infinite amounts more, in your career and in your life. Awards, and number ones, and sales, tours, and fans, and just all of it – his is better than all of that.

"This is the heart and soul of country music," she added. "The Opry has been and will always be here. The heart and soul of country music, the family. You are in it. Congratulations. Welcome to the family."

Ballerini credited Underwood with being an inspiration to her, when she was a young girl with big dreams.

"I wouldn't know what it looks like to be a female in country music without Carrie Underwood," Ballerini told PopCulture.com and other media backstage before her induction. "She's the one for me, that I've always looked up to. Not only her music, but I think she has the kindest heart. I think that she's so poised, I think that she just does everything with grace.

"I've always kind of wanted to follow in those footsteps," she continued. "I remember when Randy Travis invited her to join the Opry, and watching that video over and over again. There was just such a magical moment that was captured there."

It was especially meaningful that Underwood induct Ballerini, since their relationship began at the Opry.

"The first time I met Carrie was at the Opry," Ballerini recounted. "I was a fan. I remember I just went up to her and I thought I was just gonna say hi and take a picture like a normal person. Instead, I just blurted out, 'Girl you got soul.' I was like, what? She doesn't remember that, I don't think, which is good. When she decided to be here tonight to [induct me], it's a big deal. She's busy being famous. She's busy rehearsing for a massive world tour.

"The fact that she A, loves the Opry, and B, love women in country music enough to be here tonight is a big deal," she added.

Photo Credit: Courtesy of Grand Ole Opry/Chris Hollo