Bella Ramsey

Their Le Trône de fer (2011) character Lyanna Mormont was originally written to appear in just one scene. However, the producers liked their performance so much that they decided to keep the character in the show.

[identifying as non-binary] I guess my gender has always been very fluid. Someone would call me 'she' or 'her' and I wouldn't think about it, but I knew that if someone called me 'he' it was a bit exciting. I'm very much just a person. Being gendered isn't something that I particularly like. But in terms of pronouns, I really couldn't care less.