In the 1870s, Russia was ruled by a Czar, not a King. His daughter was not called a princess but a Grand Duchess instead. The last Russan Czar was executed in 1917.
Dr. Quinn has the patient who fell from a ladder spend the night in the Clinic. She does not stay nor does she have someone else stay. It does not makes sense for the patient to stay over night in the clinic unattended. He would be better off being home with his family.