My ancestor, Charlotte Schilling von Canstatt, performed a similar function for her friend, who eventually became Empress Maria Feodorovna, wife of Tsar Paul. Charlotte was originally hired by Duke Eugene of Wurttemberg as a companion for his daughter Sophia, or so goes the family story. There was little employment for young gentlewomen outside of working as a companion for a royal or noble house, so there was a benefit on both sides. When Sophia was chosen as a bride for Catherine the Great's son, she asked her friend to accompany her to Russia. I'm sure this was a similar situation with Ella leaving Germany for Russia. A companion with a knack for languages was not a luxury for a young woman leaving her home and family for greater responsibilities in a foreign land - she was often a source of support and encouragement. In Charlotte's case, her service at the court of Catherine the Great allowed her to make a better marriage than her former circumstances would have allowed.