Solstice is the lovable family dog of Henry and Elaine. Solstice is dying of a disease known as valley fever. Valley fever is a lung fungus that is common disease in the southwest. Both dogs and humans can contract the disease, and many often die. She is given Nizoral, which will slow the progression of the disease, but she will still eventually die. Henry is originally planning to leave the dog with Elaine's house, but when the dog runs after him, he decides to take her as a companion. It is Solstice who provides Henry with a constant companion during his trip and who gives Henry a purpose to life throughout his journey. Solstice saves Henry when his truck becomes stuck in a flood and Henry falls asleep. Solstice wakes him and pushes him ever forward. When Solstice becomes too sick to walk, Henry carries her, rather than leave her behind, showing his close relationship with her. He can relate to her dying pain, as he himself is also dying a painful death. As such, Henry keeps Solstice throughout his journey, until the very end, when he rejoins his family at Stump Creek.