Rosie Jones is Duncan's sister. She went to LIPA, Liverpool Institute for Performing Arts. She is a musician/songwriter and part of a group called the Worry Dolls. She currently resides in London.
Rosie sung a parody of the song Wrecking Ball by Miley Cyrus called Enderman for Duncan's YouTube channel, which was released on iTunes, Amazon, Spotify and other online retailers under the Yogscast Studios label. The song was released on the 1st November 2013.