Thanks for the picture, she was lovely,and it's nice to see Zenaida kept her memory alive. It is strange Felix didn't mention more about her in his book since he did discuss other dead relatives.
Since her hair is down in the picture, I guess we can assume she was less than 17. This may be the last image of her in good health,for all we know. Could it be she developed some kind of health or mental issue after that age? I know I am speculating again, but I can't get over how this lovely Yussoupov girl isn't spoken of in anyone's stories! I especially wonder about it because of Sandro, he was the same age as this sister, yet he only spoke of having a crush on Zenaida. Does this mean she wasn't in public view often? And if so why? And what killed her at such a young age? It is strange a girl of that status and beauty would not have had suitors. So many sad questions. I want to know more about this girl. I wonder if we'll ever know
Maybe that is the last pic of her in good health and this is why Zenaida loved it so much.
Another guess could be she was weakened by some fever, like scarlet fever. This was common in those days, and is what caused Helen Keller to go blind and deaf, Mary Ingalls to go blind, and Queen Alexandra of England and Princess Alice (daughter of Victoria Milford-Haven) to go partially deaf. It also caused "Beth", the sister of "Jo" in Little Women, to pass away. This was of course based on a true story. Louisa May Alcott's sister got a weakened heart from the fever, and became more or less a bedridden invalid for the last few years of her life, then she finally passed away, very young. It could have been something like that.