I’ve just finished watching the 1921 film, The High Sign, which was the first film that Buster Keaton wrote and directed. In that film, the leading lady, Ms Burkett, played ukulele — in a silent film no less, and gave a good impression that she knew what she was doing. If you’d like to see the film, it is here.
If you’d like to know more about Ms Bartine Zane (married name) you can’t do much better than looking here. The link has Mrs Zane’s account of her time working with Mr. Keaton and there are two photos of Bartine, Buster and the ukulele.