SEATTLE — At 18 months old, Claire Crosby was often found at the piano in her parents Provo, Utah, apartment playing one note and then singing the same tune. At 22 months, Claire's father Dave Crosby asked if she wanted to sing their traditional bedtime lullaby, and she sang it to him pitch perfect.

A short two years later at age 4, Claire has accumulated more than 50 million views on YouTube, appeared on "The Ellen DeGeneres Show" twice, been cast in a movie and will appear on NBC's "Little Big Shots" Sunday.

When asked why she likes to sing, Claire told the Deseret News, "Because I just like to sing with my soul. It makes me feel happy."

In January 2016, Dave Crosby published a video of Claire singing "Part of Your World."

"She was singing it everywhere we went," Crosby said. "I just noticed that she had a good little voice for a 3-year-old."

Crosby was working for Amazon at the time in the musical instruments department and had a lot of free equipment to film her. During Christmas break 2015, Crosby put the video together and published it.

"It really was just for family and friends," Claire's mother, Ashley Crosby said. "We posted just because it was so cute and something we wanted to share, but never ever thought — it wasn’t our plan to do a channel with her ever, but it was something that just grew."

Claire's "Part of Your World" video received more than 13 million views and was shown on national television across the country and websites around the world.

Since then, the Crosbys have published 41 additional videos, including music videos of Claire performing songs from "Tangled," "Mulan," "Beauty and the Beast" and others. Claire picks which songs to perform, and usually learns the music and words in less than a week.

"It’s because she’s so interested in them," Ashley Crosby said, "She’ll just grasp onto them, it’s all she wants to listen to."

Her parents agree that Claire's popularity most likely comes because of the way she sings each song.

"She just feels the music," Dave Crosby said. "The facial expressions she does, that’s just her. We don’t know where that came from."

Once Claire's video began to be shared across the country and world, the Crosbys began to have discussions about the importance of protecting their young daughter.

"Our daughter has a talent that we want to share with people, but at the same time we’ve been trying to be really careful," Dave Crosby said. "We’ve had to do a lot of balancing about what to post and not to post and opportunities that we should take and some that we should turn down."

The Crosbys have not signed Claire with an agent and consider each opportunity that comes day by day. As companies reach out to the Crosbys with different ventures for Claire, the Crosbys explained, if it's not something Claire would be interested in, they turn it down immediately.

One opportunity the Crosbys did take was for Claire to perform on NBC's show "Little Big Shots." The episode was filmed about one year ago, and it will air Sunday.

While they have enjoyed such opportunities, the Crosbys have also placed an importance on giving Claire a normal childhood.

"We’ve been really careful to not push her to do songs or put in all this time," Ashley Crosby said. "The making of the music and the production that Dave does is the bulk of the work, which he does when she’s asleep. For all that she knows, she sings in the microphone for a little bit and then she’s done."

Producing Claire's videos, however, is something that Dave enjoys. As someone who once dreamed of being a musician himself, Claire has helped inspire and remind him of his creative abilities.

"I honestly think this is going to be one of the most fun times of my life," Dave Crosby said. "I’m definitely aware that this moment in our life is super unique, and I think we’ll look back at this time period for a long time just thinking how awesome it was."