Lizzie is the mother of Amanda Shuffleup and the owner of the Shuffleup Book Shop, which she runs from the ground floor of the family home. She is a single parent, still grieving the loss of her husband, which has left her stressed and burdened by the practical demands of running a household and a business. Lizzie cares deeply for Amanda but struggles to understand her daughter’s intense involvement with Rudger, an imaginary friend only Amanda can see or hear. She often appears exasperated by Amanda’s aloof behavior and what she perceives as a fixation on make-believe, viewing it as a childish phase that distracts from real-world responsibilities. This frustration stems from her own disconnection from imagination—Lizzie has long since forgotten that, as a child, she too had an imaginary friend, a sheepdog named Fridge.

Lizzie’s role in the story is primarily that of a grounding parental figure, but she also embodies the theme of lost childhood creativity. Her inability to perceive Rudger or other Imaginaries reflects how adulthood can dull the imaginative spark. Her motivation is to protect Amanda and keep her safe in the real world, yet she inadvertently pushes her daughter away by dismissing the importance of Rudger. As the crisis escalates and Amanda is hospitalized after an accident, Lizzie is forced to confront her own grief and her daughter’s inner world.

A key moment of development occurs during the climactic confrontation with the antagonist, Mr. Bunting. When Bunting conjures a massive snake that begins crushing Amanda, Lizzie is initially powerless because she cannot see the imaginary creature. With Rudger and Amanda’s encouragement, she reaches into her own past and remembers Fridge, her old imaginary friend. By calling him forth, Lizzie reconnects with her imagination, enabling her to see the snake and allowing Fridge to incapacitate it and rescue Rudger. This act not only saves the day but also redeems Lizzie’s character: she moves from a place of skepticism and emotional distance to one of active participation in her daughter’s imaginative world. After the ordeal, she shares a tearful embrace with Rudger and Fridge, signifying a healed relationship and a restored sense of wonder.

Lizzie’s notable ability is the capacity to summon her long-forgotten imaginary friend once she rediscovers the belief in him. This power is not supernatural but rather a reawakening of the creative part of herself that had been buried by adult responsibilities. It demonstrates that imagination is not solely the domain of children, and that reconnecting with it can provide strength in moments of crisis. Her character arc underscores the value of retaining a sense of play and the emotional bonds that transcend the boundary between the real and the imaginary.