Throughout Orbiting Jupiter, characters find surrogate connections to make up for the family they lack. These connections are most relevant to Joseph, whose search for a family fuels his actions. Before Joseph and Maddie have sex, they reenact a memory he has of his lost mother. By conceiving Jupiter, they build a new family together, and he attempts to escape juvenile detention centers multiple times to reconnect with his new family.

The Hurds fill the family role for Joseph when they agree to foster him. When Mr. and Mrs. Hurd agree to help Joseph find Jupiter, they show that they have accepted Joseph into their family. Mr. Hurd fulfills the role of a father that Joseph’s biological father cannot, and Mr. Hurd embraces Joseph physically and figuratively.

Neither Jack nor Joseph have biological siblings, but the closeness of their relationship grows to resemble brotherhood. They work on chores together and build rituals that belong only to them, and they also share bunk beds and open up to one another about their emotions. While decorating the tree on Christmas Eve, the Hurds symbolically express this siblinghood with matching golden angel Christmas tree ornaments. In this way, Jack and Joseph receive equal recognition as Hurd children.