Miss Sarah Fry is described in Sharpe's Escape as being "twenty-two years old, blue-eyed, fair-haired and worried for her future."
When she was 10 her father died, and her mother died a year later. She was subsequently raised by an uncle who had reluctantly paid for her schooling, but refused to provide any kind of dowry when she had reached 18, therefore cutting her off "from the more lucrative part of the marriage market".
She became a nursery maid for the children of an English diplomat who had been posted to Lisbon, and it was there that the wife of Major Ferreira offered to double her salary if she would come to Coimbra to school her two children, Tomas Ferreira and Maria Ferreria. Without the money to pay her fare back to England, and a glowing testimonial from her previous employers, she was trapped in Coimbra with the Ferreria family.