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 Sairah 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. They welcomed twins on August 16, 2021.
She sang a cover of Rihanna's song "Only Girl (In the World)" for her X Factor audition.