The Jinx and the Pinkerton (The Pinkerton Trilogy)

Luke McCabe, Pinkerton Detective, goes undercover to investigate a matter of national security. Pretending to be married, he and Charisse Jones, a woman escaping the stigma of divorce, embark on a 2000-mile trek across the wilderness in a wagon train full of cutthroats and misfits. But traveling the Oregon Trail is never easy, especially when you throw in a Corgi, a canary, four mischievous children and a barrel full of secrets.