Arnold began training and competing in
ballroom dance competitions at a young age. When she was nine, she placed third at the
2014 World DanceSport Championships in
Paris. She ranked fifth at the
2019 WDC World Championships in
Dublin. She was paired with actor
Miles Brown under the mentorship of her sister,
Lindsay Arnold. The couple made it to the finals and finished as one of three runners-up; tying with
Ariana Greenblatt and Artyon Celestine (with mentor
Brandon Armstrong) and
Mackenzie Ziegler and Sage Rosen (with mentor
Gleb Savchenko). ;Notes
Dancing with the Stars Arnold was the first pro from
Dancing with the Stars: Juniors to be cast in the
main competition series following its cancellation. She was announced as a professional dancer for
season 32 and was partnered with media personality
Harry Jowsey. Despite consistently earning low scores and criticism from the judges, audience voters allowed the couple to stay in the competition until they were eliminated during the quarterfinals on November 21, 2023, finishing in sixth place. For
season 33, Arnold was paired with Olympic artistic gymnast
Stephen Nedoroscik. They reached the finals and finished in fourth place on November 26, 2024, making Arnold the first
Dancing with the Stars pro born in the 21st century to advance to the finale. Arnold and Nedoroscik's
contemporary-based
freestyle routine to
Coldplay's "
Viva la Vida" was acclaimed by critics and viewers. Rebecca Iannucci from
TVLine named it the best dance number of the year. For
season 34, Arnold was paired with
Scott Hoying of the
a cappella group
Pentatonix. They were eliminated during the sixth week of competition on October 21, 2025, finishing in tenth place; Arnold's lowest placement to date.
Season 32 Celebrity partner:
Harry Jowsey ;Notes
Season 33 Celebrity partner:
Stephen Nedoroscik ;Notes
Season 34 Celebrity partner:
Scott Hoying ;Notes == Reception ==