‘Nashville’ casts 13 and 6-year-old YouTube viral singing stars Lennon and Maisy Stella

Tiffany Lee

Another viral video success story (kind of)! The talented, adorable and innovative singing sisters Lennon, 13, and Maisy Stella, 6 (awesome names, by the way), known for their cover of Robyn's "Call Your Girlfriend," are guest-starring in this season's most anticipated new show, ABC's "Nashville."

The Stella sisters will be playing Maddie and Maisy James, the daughters of country music falling star Rayna James (Connie Britton). The girls will be performing in a school talent show on what is scheduled to be the third episode.

Lennon and Maisy were cast after the pilot was shot and way before the sisters even went viral on YouTube, so they're technically not a YouTube discovery. But the "Nashville" casting directors certainly had a sharp ear for raw talent. Harmonizing perfectly while playing empty butter tubs as a unique percussion accompaniment (only kids can find music in everyday things so easily!), the Stellas' Robyn cover video has so far received over 8.5 million views.

[Related: Watch the pilot for 'Nashville']

Maisy originally auditioned for one of the parts and told casting agents about her singing sister. Once they were seen performing together, the search for the James sisters was over!

"Nashville" producer R.J. Cutler told The Hollywood Reporter, "Even though the parts of Rayna and Teddy's (Eric Close) daughters had been written for a 6- and an 8-year-old, we decided on the spot to change the roles to fit Maisy and Lennon's ages. Listening to them sing literally brought tears to our eyes. I'm not just saying that. Their voices moved us to tears. We knew we had to cast them."

What makes the Stella sisters so unique is that they don't rely on the small kids/big voices formula that is nowadays a dime a dozen on YouTube. Softer, jazzier with a little country twang, Lennon's and Maisy's enchanting voices are more attuned to the Norah Joneses and Ingrid Michaelsons of the world. Their talent -- not some over-the-top personalities -- shines through.

Plus, with covers of The Swell Season, Imogen Heap, Jason Mraz, and John Lennon (of course), their tastes in music are top notch! Not only are they moving singers, the girls also learned to play the guitar and the piano as young as five years old.

Starring "Friday Night Lights" alum Connie Britton as James and "Heroes" alum Hayden Panettiere as the up-and-coming singer Juliette Barnes, "Nashville" follows the battling stars as they're forced together to help revive James' career and promote Barnes'. The critically-acclaimed drama also features original music and real vocals provided by the actresses themselves!

"Nashville" premieres on October 10 at 10 PM on ABC.

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