Culture and Identity
Indigo, her sister, and her mother are all a part of the Sand Lizard Clan. To an outsider, this may just seem like a weird, made up name, but to them, it is who they are. They are part of a unique culture group that was initially expelled by white men hundreds of years ago. However, they have grown resilient to threats, and find that keeping their culture alive is more important that conforming to the norms of society.
Segregation
Indigo and her sister are victims of extreme segregation, both because of their culture and because of their gender. The whole clan is at risk for trouble because the neighboring city has many people that don't like them, and they would be all too happy to take away their children to send them to a boarding school. Eventually, this is where Indigo ends up, and she is verbally abused because of her race. Sister Salt is sent to prison, and there she is also verbally abused and raped because no one has any respect for who she truly is.
Love
With the power of love, Indigo is able to get through all of the troubles in her life. Initially, she had the love of her sister and her mother. This was while she was a young child, and they were there to guide her through life. When she was sent to the boarding school, she experienced what it was like to have no one by her side telling her that she was loved. However, she knew that somewhere, her mother was out there, still caring for her. When she was adopted by a white couple, Edward and Hattie, she realized that the power of love extends to all human kind, and it is a large factor in helping people get over their cultural biases.
