This adorable footrest is in Fern Bedaux's bedroom at Candé. We have a soft spot for mini dachshunds (or teckels, as they are called in France). In London we were aunty and uncle to sisters Tiger and Sponge, and got to look after them sometimes when their doting owners were on holiday or away on business.
The docent told me that Fern didn't actually use it as a footrest, but to hold the pages of books open.
If you are interested in Fern Bedaux (if you know her name at all, it will probably be as the hostess of the Duke and Duchess of Windsor's wedding) there is a well researched blog post here. She was a fascinating person, full of unexpected redeeming features and contradictions. Wallis Simpson liked her, and I doubt you could say that about many women, although I'm not sure if it is necessarily a positive attribute.