Philomène is a nun and Vaillant’s sister. Because their mother died at such a young age, the two Vaillant siblings are unusually close; Vaillant struggled to leave his sister behind in France when he came to the U.S., and Philomène remains his dearest correspondent throughout the novel. In addition to taking care of Vaillant and Latour from afar, making them new cassocks and sending provisions, Philomène takes great pleasure in living vicariously through her brother’s frontier adventures.