Became known after winning The X Factor as a member of the popular all-girl group Little Mix. They were the first group to win the competition and signed with Simon Cowell's record label, Syco Music.
She attended a Theater School in London at the age of 11 and she later worked as a waitress at Pizza Hut.
She helped her group Little Mix release two #1 singles on the UK charts with "Cannonball" and "Wings."
She was raised by her parents, John Pinnock and Deborah Thornhill, and has two sisters named Sarah and Sian-Louise. She dated Jordan Kiffin from 2013 to 2016. In 2016, she began dating soccer player Andre Gray and the couple got engaged in 2020.
She sang a cover of Rihanna's song "Only Girl (In the World)" for her X Factor audition.