I never discover anything while cleaning but dust and more dust! This bedroom is at Medford Hall, the home of her cousins the Hyde Parkers. All the relatives' homes I've seen are stately mansions and they all should have a sign out front saying "Beatrix Potter Slept Here"
I love here interior renderings and you can see all four here: https://www.bbc.com/news/uk-england-suffolk-36716973
One picture was discovered by Lady Hyde Parker, who lives at Melford Hall with her husband, Sir Richard, where Potter took regular holidays between 1899 and 1916. The article contains a beautiful photo of Medford Hall.