Kildunne's England debut came in 2017, when she scored a try for the England 15s in a match against
Canada. and also in the Six Nations after England's 46–0 win over Scotland on 13 April 2024. In the summer of 2018, Kildunne transitioned to England Women's Sevens team as it fought to—and did—qualify for the
2020 Summer Olympics. Kildunne made her return to XVs rugby but missed the first two events of the 2019 World Series due to injury. She went on to play eight of England's matches of the competition and scored three tries for her country. She was named in the
England squad for the delayed
2021 Rugby World Cup held in New Zealand in October and November 2022, and played in the final which England lost to New Zealand to finish as tournament runners-up. In June 2024, she was named in the British squad for the Olympic Games. The team finished seventh. In November 2024, she was named
World Rugby Women's 15s Player of the Year at the
World Rugby Awards. She was called into the
Red Roses side for the
2025 Six Nations Championship in March. On 29 March 2025 she was named Player of the Match in a 67–12 win over Wales in the Women's Six Nations. In July 2025, she was named in the England squad for the
2025 Rugby World Cup. Having scored two tries in England's semi final victory over France, on 27 September, Kildunne played in her second consecutive World Cup final, and scored the opening try for England as they beat Canada 33–13 at Twickenham to become world champions. During the 2026 Six Nations Championship Kildunne scored her fiftieth international try in an 84–7 win against Scotland on 18 April. ==Personal life==