Katia lives in Zigfridstrasse 27, Zurich.
In 1904, Karl von Toten sent her a letter, explaining his success. It is unknown if the letter was ever recieved by her.
It is very likely she is Von Toten his wife. This was never confirmed. There is a painting in Karl von Toten his house of an elderly woman. It also is not confirmed that this is Katia or his wife or both.