She was 16.
"It is with the deepest sorrow we have to announce that on Sunday, 7 April, Mya-Lecia Naylor, very sadly, died," A&J Management said Wednesday on Twitter. "Mya-Lecia was hugely talented and a big part of A&J, we will miss her greatly."
The actress died after she collapsed Sunday and the cause of her death is not yet known, the BBC reported.
Naylor began acting as a toddler on the show Absolutely Fabulous. Before long, she was being cast in TV movies and miniseries.
Her big break came in 2014 when she cast in Millie Inbetween as the character Fran. After four years on that show, she landed the part of Mya on Almost Never.
Those two shows with CBBC are what she was best known for.
In a statement Wednesday, CBBC said Naylor "was a much-loved part of the BBC Children's family, and a hugely talented actress, singer and dancer."
Game of Thrones actress Nathalie Emmanuel, who is from England and was with the same management company as Naylor, took to Twitter to share her condolences.
Very sad to hear the tragic news of Mya-Lecia Naylor’s passing. She was a part of the @aj_management family who represent me in the UK. Although I didnot know her personally, I wanted to send my condolences to her family, friends and colleagues at this difficult time ❤️— Nathalie Emmanuel (@missnemmanuel) April 17, 2019
"Very sad to hear the tragic news of May-Lecia Naylor's passing," she said, adding, "Although I did not know her personally, I wanted to send my condolences to her family, friends and colleagues at this difficult time."
CBBC said that the news of Naylor's passing is "very upsetting," and invited fans to share feelings with friends and family.
"We will miss her enormously and we are sure that you will want to join us in sending all our love to her family and friends," the network said.
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Notable deaths of 2019