Sophia Grace and Rosie Sing New Taylor Swift Song on Ellen, and They Were In For a Surprise (VIDEO)

Sophia Grace and Rosie, the adorable British cousins who have become regular visitors to the Ellen DeGeneres show, caught up with Ellen on Monday.

The pink-loving, tutu-wearing duo performed Taylor Swift’s “I Knew You Were Trouble,” and it was maybe their best performance yet. Sophia Grace has an amazing voice and while her younger cousin Rosie didn’t sing, she had some great moves:

The girls, who rose to fame after their mom posted a YouTube video of them singing Nicki Minaj’s “Super Bass,” have made multiple appearances on the Ellen show since 2011. Ellen even sent them to cover the red carpet at the Grammys and the VMAs, where they got to interview their favorite celebrities.

On Monday, Ellen had a big surprise for them: copies of their new book, Tea Time with Sophia Grace and Rosie, released Feb. 4 from Orchard Books. Check out the girls’ reactions:

Interestingly, while Sophia Grace is extremely talkative and extroverted on camera, she is actually quite shy in her normal life, her father told the Huffington Post’s Lisa Belkin in 2012.

“She’s better at talking with adults than children her own age,” he told Belkin. “When she goes on these programs she seems to be able to talk to the adults as if she’s an adult. When she’s around kids she gets tongue-tied.”