Millie started playing hockey at the age of 10 at Buckingham hockey club, where she played her first Premier League Game at the age of 15. She went on to play 3 full premier seasons at the club. Now attending Exeter University, she plays for ISCA/University of Exeter in the Division one South League and plays for the university’s BUCs team in the Premier Division. Millie made her senior international debut for Wales in 2021 at the European Championships in Prague, going on to play in the World Cup Qualifiers in Pisa. In 2022, Millie was selected for Great Britain’s Elite Development Programme.