Janie’s gold earrings, and her response to Pip’s suggestion that she sacrifice them to make the invisibility serum the children need to save Benjamin’s father, symbolically highlight her growth and dynamism as a character. She describes how her grandmother Helen, to whom the earrings belonged, tried to behave in a sophisticated and elegant way but ultimately couldn’t help being silly and warm. Janie is similar. Though she used to attempt to embody the sophistication and poise of Katharine Hepburn, hoping “to be elegant like [her] nana Helen had always wanted to be” (161), she realizes that her grandmother would “want [them] to find [Benjamin’s] father” (161). Helen couldn’t reject her earnest and fun-loving nature, just as Janie can’t abandon her loyal and loving personality. Thus, Janie sacrifices her grandmother’s earrings to make the invisibility serum that the children hope will enable them to save Burrows, even though they’re “the only things of hers [Janie] ha[s]” (161). Janie doesn’t yet realize that she shares her grandmother’s sweetness and high-spiritedness, a far more significant homage to her grandmother’s character and memory than wearing the woman’s jewelry.

Sarah Pennington’s willingness to sacrifice her gold necklace for the same reason indicates her real nature. Though she begins the text as a bit of a snob, by the end, she has a crush on Pip, a lower-class boy from London’s East End. She knows that the children won’t be able to restore her melted-down necklace to its original state, yet she gives it to them anyway. Pip tells her, “I said you’re the kind of girl who would naturally help” (230), and he’s right. She later provides the children with warm coats, clothes, and boots for their journey to Russian waters. Giving them her gold necklace, even without understanding what it’s for and knowing full well that they’re being dishonest about its use, shows her true, helpful nature.