In June DiCello competed at the Junior World Championship Trials. She placed second behind Skye Blakely and was named to the team to compete at the 2019 Junior World Championships alongside Blakely and Sydney Barros. Together the team won bronze, finishing behind Russia and China. Individually she finished fourth in the all-around behind Russians Viktoria Listunova and Vladislava Urazova and Ou Yushan of China. She was the only competitor that qualified to all four event finals. On the first day of event finals DiCello won gold on vault, finishing ahead of competitors Jennifer Gadirova of Great Britain and Urazova and finished sixth on uneven bars. On the second day of event finals she won bronze on balance beam behind Elena Gerasimova of Russia and Wei Xiaoyuan of China and placed seventh on floor exercise.