Welcome to the weird world of YouTube, where tutu-wearing child rappers rule and nothing has the power to go nuclear like a pair of yabbering, diaper-clad babies.

With the meteoric rise of cousins Sophia Grace Brownlee and Rosie Grace McClelland in the US this week, there's a lot to be said for the influence of pint-sized stars on YouTube.

Sophie and Rosie found international fame after a frankly genius video of them performing Nicki Minaj's song Super Bass (below) went viral on the channel last month.

Their rousing rendition of the rap tune won them an army of fans around the world, along with an invitation to appear on The Ellen DeGeneres Show.

The tiara-toting duo went on the programme last week, where they got to meet their idol Nicki Minaj in person, prompting massive media coverage and an even larger online following.

With talks of a record deal in the pipeline, we take a look at the song that started it all - along with other youngsters who've become YouTube sensations with their hilarious video antics.

From swearing toddlers to biting babies, find out more below...

1. Super Bass By Sophia Grace Brownlee

Pint-sized pop stars Sophia Grace Brownlee, eight, and her five-year-old cousin Rosie Grace McClelland became overnight sensations for this heartfelt and high-energy rendition of Nicki Minaj's hit "Super Bass" on YouTube. The stirring rap performance won them a prime time slot on The Ellen DeGeneres Show.

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