Cultural, social and legal markers of elite maturity were shifting over the central Middle Ages, generating changes which affected how young people experienced late childhood and early adulthood. This chapter examines how some of these developments unfolded in relation to child kingship. It reinforces an argument which recurs throughout the book: that change over time was more substantial than cultural and political differences between kingdoms. First, the chapter examines the shifting significance of a boy king’s knighting. The acceptance of arms had been part of a child king’s rite of passage to young adulthood in the mid-eleventh century but, a century and a half later, knighting had instead become a crucial element in a royal child’s rite of passage to kingship. Then the chapter turns to consider the seals produced for and used by boy kings, emphasising the increasing diversity in seal forms and their creation from the thirteenth century. A crucial theme throughout the entire discussion is how kingship altered a child’s progression from boyhood to manhood, distinguishing a boy king’s experience of adolescence from other elite youths.