It was a dream come true for two lil YouTube stars on The Ellen DeGeneres Show today. We all sighed a collective "ohhh" when Sophia Grace Brown Lee, 8, and her cousin Rosie, 5, donned pink ballerina tutus and sparkly princess crowns to masterfully rap their way through Nicki Minaj's "Super Bass" last week. The tots became overnight sensations, with their video racking up more than 7 million views from fans around the world. Today, the duo appeared as Ellen's guests, where they were surprised by the rapper herself, who urged the girls to stay in school before joining them for an "impromptu" duet. Check it out below — their reaction is great!