Most of the characters in The Thief Lord are either orphaned, mistreated by their guardians, or both. Esther and Max Hartlieb, for example, have no interest in their orphaned nephew Prosper and see nothing wrong with separating him from his beloved little brother. Scipio’s parents are alive but do not provide him with a loving or supportive home; the same is true of Hornet. The unreliability of the characters’ blood relations makes the found family they create amongst themselves all the more important. Although Prosper and Bo’s aunt and uncle are wealthy, they feel more at home in an abandoned and unheated movie theater infested with rats. This shows that a home isn’t a location but a feeling of love and fellowship.

When Esther and Max hire Victor to bring Prosper and Bo back, it pits the two different ideas of family against one another. By their own admission, Esther and Max don’t especially like children; their interest in adopting Bo seems to reflect a sense that it’s the appropriate thing to do rather than any affection. When they finally get Bo back, they are quick to reject him the moment he misbehaves. By contrast, the children at the Stella all demonstrate deep loyalty to one another.