The Warriors Apprentice

This is the second book in the saga of the Vorkosigans and introduces Miles Vorkosigan. At age seventeen, Miles is allowed to take the entrance exams to the elite military academy; he passes the written but manages to break both his legs on the obstacle course, washing out before he begins. Blaming himself for the death of his aged grandfather, Miles leaves for the Beta Colony to visit his grandmother accompanied by his bodyguard, Sergeant Bothari and Botharis daughter, Elena. Rumors of Miless mercenary operations place his father Aral under political attack, and Miles must make his way home to stop the plot.