In 2011, Erato, a female vocal trio comprised of Ebba Lovisa Andersson, Amanda Wikström and Petra Brohäll, covered Robyn's "Call Your Girlfriend" using just their voices and a few plastic cups.

Now, two young sisters are doing their own version of Erato's cover of Robyn's song, armed with just two empty plastic containers and a couple of microphones. The result is simply amazing.

As you'll see from their names floating above their heads, the girls are called Lennon and Maisy. They are only 12 and 8 years old, respectively. (Paging Ellen DeGeneres!)

Big sister Lennon is the main vocalist, while little sister Maisy provides the harmonies. To put that into perspective: even adult singers struggle with harmonies, so the fact that an 8-year-old has mastered them is pretty impressive.

To watch more of Lennon and Maisy's covers, click through the gallery below.

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  • "Ho Hey" - The Lumineers

  • "Christmas Coming Home"

  • "Happy Birthday, Harry"

  • 'I Won't Give Up' Jason Mraz cover by Lennon and Maisy Stella

    Lennon 12 and Maisy 8 sing their version of Jason Mraz's I Won't Give Up. These girls are truly amazing. The Stella sisters :) Thank you to Matt Blair for doing this video :)

  • 'When Your Minds Made Up' The Swell Season cover by Lennon Stella 12 & Maisy Stella 7

    12 year old Lennon Stella sings When Your Minds Made Up by The Swell Season. Her sister Maisy Stella 8, sings harmony. It'll make you smile & cry :)

  • Ingrid Michaelson 'You And I' cover by Lennon 10 and Maisy 6

    sisters Lennon 10 and Maisy 6 sing Ingrid Michaelson- you and I cover

  • Live at KX 94.7 -- Lennon and Maisy Stella - When Your Mind's Made Up

    Live at KX 94.7 -- Lennon and Maisy Stella - When Your Mind's Made Up

  • 'Call Your Girlfriend' Robyn/ Erato cover by Lennon & Maisy Stella

    12 and 8 year old sisters Lennon and Maisy sing their version of Robyn/Erato Call Your Girlfriend.

  • Jessie J Price Tag cover by Lennon & Maisy Stella

    Lennon 12 and Maisy 8 sing 'Price Tag' by Jessie J at Pucketts in Leipers Fork, TN

  • Fine Soon - The Stellas (cover by Lennon and Maisy)

    Our children, Lennon (with her grade 4 class) and Maisy (with her SK class), perform a song written by us (the proud parents!) at the school assembly on May 1, 2009. It's even cuter that they're reading buddies.

  • 'Till There Was You' cover by Maisy Stella 7

    Maisy Stella 7 yr old performs Till There Was You @ The Rutledge during Tin Pan South 2011 With Steel Magnolia

  • 'Secret' Missy Higgins cover by Maisy Stella 7

    7yr old Maisy Stella plays and sings Secret by Missy Higgins. Sooo good!

  • John Lennon 'Imagine' cover by Lennon Stella 10

    Lennon Stella 10 years old singing her version of John Lennon's Imagine.

  • Lennon Stella - 11yr old - When It Falls Apart - Matthew Perryman Jones cover

    Lennon Performs 'When It Falls Apart' - by Matthew Perryman Jones @ The Rutledge during TIN PAN SOUTH with Steel Magnolia 2011

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