The painting, thought to be lost, was rediscovered in 1914. It is described in the book
'Life of Charlotte Brontë' by Elizabeth Gaskell (pictured), so we know the seating arrangement in the portrait. More info about the portrait and its discovery here:
npg.org.uk/collections/searc… (https://www.npg.org.uk/collections/search/portraitExtended/mw00797/The-Bront-Sisters-Anne-Bront-Emily-Bront-Charlotte-Bront)
https://nitter.moomoo.me/GrecianGirly/status/1654208588766760960#m