Blood Sisters: Everyone Has an Evil Twin — D.J. Bershaw

An alternate history in which a nuclear exchange severely damaged the United States. Forty years later, recovery is nearly complete, and Megan Connolly and Farrell Gray attempt to go to Pendleton, Oregon, with their four-year-old twin daughters. A cross-time adventure with elements of shopping. Instead, they flee for their lives across the state, pursued by Mormon gunships, desperately trying to reach a crossing point from which they can return to our timeline. Their situation worsens when Megan's alternate self crosses their path, putting the twins and their mothers in the crosshairs of the evil Compliance and its desperate leaders, who see their power waning and their hold on society crumbling.