The Islevale Cycle, book 1: Time's Children
David B. Jackson et David B. Coe2018

Fifteen year-old Tobias Doljan, a Walker trained to travel through time, is called to serve at the court of Daerjen. The sovereign, Mearlan IV, wants him to Walk back fourteen years, to prevent a devastating war which will destroy all of Islevale. Even though the journey will double Tobias' age, he agrees. But he arrives to discover Mearlan has already been assassinated, and his court destroyed. The only survivor is the infant princess, Sofya. Still a boy inside his newly adult body, Tobias must find a way to protect the princess from assassins, and build himself a future... in the past.

Titre original : The Islevale Cycle, book 1: Time's Children (2018)