They're baaaaack! Sophia Grace & Rosie made their triumphant return to 'Ellen' to perform a cover of Taylor Swift's 'I Knew You Were Trouble.' As usual, Sophie Grace took leading singing duty and Rosie provided some sassy choreography.

The two girls totally nailed their performance and Sophie Grace was practically shrieking with excitement as she walked over to Ellen. Who knows, maybe 10 years from now these two will put out their own official single?