For much of Jeannette’s childhood, Dad’s promise to build the Glass Castle represents both the family’s hope and Jeannette’s hero worship of Dad, but, as Jeannette grows older, the castle comes to symbolize his broken promises. Like Dad’s bedtime stories that portray him as a hero, the image of a glass castle seems larger than life and carries fairy-tale connotations. Jeannette cannot help but believe in Dad’s beautiful plan because as a child she sees Dad as the man from his stories, brilliant and talented. Jeannette’s belief in the Glass Castle and her faith in her father both disappear around the time that the family starts dumping garbage in the hole meant for the foundation. The construction of a glass castle requires not just imaginative genius, but also the dedication and effort Dad lacks. As time passes and Dad’s alcoholism reaches crushing new lows, the Glass Castle turns into a symbol of impossible dreams, fragile as glass.
Dad giving the children stars as Christmas gifts represents both the family’s anti-materialistic values and their belief in their own specialness. Mom and Dad insist the stars make better gifts than toys because the stars will last forever. While Dad likely decided on the star ruse to make up for his inability to afford gifts, it is consistent with the Walls family’s philosophy that prioritizes experience and adventure over material possessions. Accordingly, we see the true value of the gift lies in the moment each child has with Dad in which he shares his knowledge of space. Nevertheless, Dad’s claiming of the stars has a dark side of entitlement. He tells Jeannette that he can give the kids the stars because no one has claimed them yet, comparing the gift to Christopher Columbus claiming the Americas. However, Columbus didn’t claim empty land, but instead stole land already occupied by multiple nations. While Dad’s star gifts don’t have colonial results, they are still false gifts because the stars cannot belong to the Walls children simply because Dad says so. In this sense, the stars follow Dad’s belief that they are exceptional people whom the rules don’t apply to.
The Joshua tree symbolizes Jeannette and the extreme environment she grows up in, as Joshua trees grow gnarled and almost entirely sideways in the desert’s harsh winds. When Jeannette wants to dig up a sapling and replant it in a less extreme environment where it could grow straight and tall, her impulse suggests that she might also prefer a less hazardous upbringing. Mom’s insistence that a protected Joshua tree would lose what makes it special reveals her larger philosophy that strength and beauty come from hardship. When Jeannette creates a more ideal environment for herself in New York City, she must reconcile her new surroundings with her identity as a person shaped by harsh conditions. In this light, we can read her rejection of Eric, with his stability and wealth, as an acceptance of at least some of Mom’s ideas about the Joshua tree. Jeannette marries John, who sees her scars as proof of Jeannette’s strength, which echoes her mother’s view of the beauty of the Joshua tree.