“I’m trying not to be selfish. But it’s hard.”

One of Cat’s central conflicts is the tension between her responsibility as an older sister and her desire to gain independence and a unique identity apart from her family. Cat is approaching adolescence and wants to find out who she is, and when she is torn away from her home and friends to move for her sister, she feels cheated out of a normal life. Cat experiences periods of guilt over wanting independence, because she also desperately wants to protect and care for Maya.

“Maya has cystic fibrosis. It’s a thing you’re born with. It affects breathing and digestion. And there’s no cure.”

One of the traits that most heavily characterizes Maya and propels the plot of the story is her disease. Maya’s CF is debilitating and leaves her unable to engage in normal activities much of the time. She ends up in the hospital after hiking up to the mission and is left behind on Halloween when Cat trick or treats. Maya’s CF is also what leads the family to move to Bahía de la Luna in the first place, as her parents hope that the damp, salty air will aid her breathing. What Maya experiences is the opposite; she gets sicker and requires a breathing tube.