Nikita Pearl Waligwa, one of the young stars of Disney's Queen of Katwe, died on Sunday after a 4-year battle with brain cancer. She was 15 years-old.

The rising actress played Gloria in the 2016 film, based on the life of Chess prodigy Phiona Mutesi, which also starred Madina Nalwanga, Lupita Nyong'oand David Oyelowo.

Waligwastood out in a scene in which she taught Phiona—who went on to excel in several international chess tournaments—the rules of the game. A pleasant presence on-screen, she delivered the memorable line: "In chess, the small one came become the big one."

The news of her passing was first announced via the Twitter page of the secondary school she attended in Uganda. "Fare thee well Nikita Pearl Waligwa," read the announcement. "You were a darling to many and we have lost you to brain tumor at such a tender age. Nikita was in S.3. Rest in Perfect Peace dear."

According to BBC Africa, the actress was first diagnosed with a brain tumor in 2016, after which the film's director Mira Nair, helped raise funds to send her to India for treatment. While she was found to be tumor-free in 2017, another appeared last year.

Supporters, fans and co-stars, including Nyong'o, Oyelowo and Bobi Wine have been sharing heartfelt tributes to the young actress and reflecting on the courage and strength shown in battling her brain tumor.