The Lawyer and the Laundress by Christine Hill Suntz

Lawyer James Kinney isn’t looking for love, and laundress Sara O’Connor doesn’t want to be found. When their paths cross in a British colony on the brink of rebellion, a marriage of convenience may be their best hope of survival.

Canada, 1837. Widower James Kinney knows his precocious daughter, Evie, needs more than his lessons on law and logic, but Toronto offers few options. Classes with the neighbor children seem ideal until James discovers Evie is secretly spending her time with Sara O’Connor, a kind and mysteriously educated servant. For propriety’s sake, James forbids their friendship. But then Evie falls victim to the illness ravaging the city, and James must call upon Sara’s medical knowledge and her special bond with Evie to save his daughter’s life.
When Sara’s presence in his household threatens scandal, however, James offers an unexpected solution: become his wife, in name only, and help him raise Evie to be a proper young lady.

If Sara can ignore the sparks she feels when they’re together, his logical proposal could keep her secret secure forever. But soon, the forces of rebellion unravel their tidy arrangement. When James is accused of treason, Sara must find the courage to face a past that could save her husband’s life.