Marie-Grace is worried. Yellow fever is raging through New Orleans. The orphanage where she and Cécile have been volunteering is becoming crowded with children who have lost their parents to the dreadful disease. And now someone Marie-Grace cares about is terribly ill. When the chance comes to help, Marie-Grace takes it. She knows she can make a difference. But will this horrible fever cause Marie-Grace to lose the home and family she loves? Includes an illustrated Looking Back essay about health and medicine in the 1800s. The story continues in the sixth book in the series: Cécile's Gift.