To this day, a video of Sophia Grace and Rosie performing their energetic rendition of 'Super Bass' alongside Nicki Minaj on The Ellen DeGeneres Show is the talk show's most viewed content on YouTube. More than 144 million people have watched it.
Sophia Grace and Rosie, then eight and five years old respectively, were dressed in pink fairy tutus when they captured the world's hearts with their enthusiasm, innocence and insane talent in 2011.
The viral video saw the duo gain international fame: Sophia Grace became known as the crazily gifted singer with a promising future; and her cousin, Rosie, as the fiercely loyal sidekick that every woman deserves.
Watch a snippet from the iconic episode below. Story continues below.
They appeared regularly on the talk show conducting red carpet interviews, taking trips to toy shops and performing covers of their latest favourite song.
Social media simply could not get enough of them. They even had their own kid's movie made in 2014, Sophia Grace and Rosie's Royal Adventure.
But 12 years later, the two little girls are, well, no longer little girls.