Both books are based on a fictitious 1870s Brides-for-Indians program in which the government agrees to send 1,000 white women to the Cheyenne as brides, in exchange for an equal number of horses.

She elaborated: "Fergus is still a child of a w****house but he helps him get away from those guys and again, sometimes we just have to simplify things because we just can't get it all in.