Dead Heat by Patricia Briggs — book slip

Charles and Anna, mated werewolves, embark on a personal trip to Arizona, but their plans are derailed when they encounter a dangerous Fae being. This creature is replacing human children with simulacrums, escalating the Fae's cold war with humanity. As Charles and Anna find themselves in the crossfire, they must navigate the complexities of their bond and the supernatural threats that surround them.

From the world of Mercy Thompson, this Alpha and Omega novel is perfect for fans of Ilona Andrews and Nalini Singh.