This essay explores a series of affective, sexual and temporal disturbances that Shakespeare's child characters create on the early modern stage and that lead these characters often to their deaths. It does so by turning to the murdered princes of Richard III and the ultimately extinguished boy-king Arthur of King John. A pervasive sentimentality about childhood shapes the way audiences and critics have responded to Shakespeare's children by rendering invisible complex and discomfiting erotic and emotional investments in childhood innocence. While Richard III subjects such sentimentality to its analytic gaze, King John explores extreme modes of affect and sexuality associated with childhood. For all of the pragmatic political reasons to kill Arthur, he is much more than an inconvenient dynastic obstacle. Arthur functions as the central node of networks of seduction, the catalyst of morbid displays of affect, and the signifier of future promise as threateningly mutable. King John and Richard III typify Shakespeare's larger dramatic interrogation of emergent notions of childhood and of contradictory notions of temporality, an interrogation conducted by the staging of uncanny, precocious, and ill-fated child roles.