In "The Year of Lear: Shakespeare in 1606," James Shapiro explores the tumultuous period of King Lear's creation, focusing on how the play reflects the complex dynamics of family relationships and betrayal. Central to the narrative is the painful experience of parental disappointment, epitomized by Lear's tragic realization of his daughters' ingratitude. The quote, "How sharper than a serpent's tooth it is to have a thankless child," captures Lear's anguish, highlighting the severe emotional toll of having a child who lacks appreciation and loyalty.

Shapiro delves into the broader themes of loyalty, power, and the vulnerability of parental figures. The quote not only serves as a poignant expression of Lear's despair but also resonates with the era's social and familial issues. The exploration of thanklessness in familial bonds serves as a cautionary tale, reflecting the profound pain that stems from betrayal within the very family that is expected to provide love and support.