They're calling her the 'American Adele'

When 18-year-old Molly Kate Kestner first started putting videos of herself singing on YouTube, it was mainly as a way to stay in touch with friends and family. Now, thanks to an original song that's gone viral, she's on her way to becoming an international sensation.

It's easy to see why - listen to those pipes! Those vocals were enough to get Kestner attention from celebrities, national media and record labels.

The song really went viral when 'Star Trek' star George Takei shared it on his Facebook page, saying, "Has America found its young Adele? I'm nearly breathless from listening."

Since then, it's been a whirlwind for the high school senior, leading up to an appearance on "Good Morning America" Wednesday.

"Incredible voice. You received tweets from stars like Ashley Judd who says she wept and wept. You had to be overwhelmed by that."

KESTNER: "Yeah, overwhelmed would be an understatement."

On May 6th, Kestner tweeted she'd recorded a studio version of the track, titled "His Daughter," and it was soon available for sale on iTunes.

Fellow songstress Jordin Sparks tweeted her support of Kestner's "touching" song on Tuesday.

Kestner has been posting covers and original songs to YouTube since 2012. She now has more than 30 videos and more than 8 million views total, but none of her songs have taken off like "His Daughter."

Kestner wrote the emotional ballad a year ago based on other peoples' stories. But she didn't post it to YouTube until after she sang it as a solo at her senior choir concert.

ABC interviewed Kestner, who says she recorded the video with her cracked iPhone. She said:"I wasn't thinking, 'Oh, this could be a huge hit. It was another song I was recording. ... That was my first take."

As seen on Instagram, Kestner has been traveling around the country following the song's success, reportedly meeting with record labels.

But Kestner told Minnesota's Austin Daily Herald any money she makes from the song will be used to help her pay for college. "Some people want to make music to be famous, and that's totally OK. I just want to help people with my music. I want to lift them up and make them feel better about things."