[3] Kelly qualified for the semi-finals in the 200 metres on her senior debut, aged 17 years-old, at the 2018 British Indoor Championships in Birmingham.

[4][5] After stepping up to 400 metres, Kelly became the English U23 champion in 2021, in only her fourth outdoor race over the distance.

[8] She was selected for the Great Britain squad at the 2023 European Indoor Championships held in Istanbul as part of the 4x400 m relay team.

[11] In April 2024, she was selected as part of the British team for the 2024 World Athletics Relays in Nassau, Bahamas.

[14] On 5 July 2024, she was named in the British 4x400 metres relay squad for the 2024 Summer Olympics, where she won a bronze medal.