Nikita Pearl Waligwa, who played Gloria in the 2016 Disney film Queen of Katwe, has died at 15.

Her death was announced by Ugandan media, who confirmed that Waligwa died Saturday night in Uganda as a result of a brain tumor. She was first diagnosed in 2016.

Queen of Katwe is based on the true story of Ugandan woman Phiona Mutesi, whose life changed when she took up the game of chess and, despite not being in school, became so successful that she became a chess player on the international stage. The film also starred Lupita Nyong'o as her mother and David Oyelowo as her chess teacher. Waligwa played Mutesi’s friend.