I was not aware of that, but a quick look shows that the officiel mascot of Plan 9 actually was drawn by Renée French (see http://glenda.cat-v.org/ ). I don't know whether the specific mascot for the uxn project also comes from her or not, but we know that Devine and Rek use the Plan 9 OS (see https://100r.co/site/about_us.html ).