Hannah recommends Ghosts by Raina Telgemeier

Cat and her family move to a new town with a climate that is better for her little sister Maya's cystic fibrosis. Bahía de la Luna is damp and foggy, and Cat's new classmates are obsessed with ghosts. Maya wants to meet one, but all Cat can think about is her sister's fragile health. As Día de los Muertos draws near, Cat has some decisions to make about her new friends and her family. The illustrations are clear and eye catching and the plot sweeps you in immediately. This is not a spooky story, rather an examination of the unbreakable bonds that can continue long after death. A sweet and magical story.
Publisher Description:
Catrina and her family are moving to the coast of Northern California because her little sister, Maya, is sick. Cat isn't happy about leaving her friends for Bahía de la Luna, but Maya has cystic fibrosis and will benefit from the cool, salty air that blows in from the sea. As the girls explore their new home, a neighbor lets them in on a secret: There are ghosts in Bahía de la Luna. Maya is determined to meet one, but Cat wants nothing to do with them. As the time of year when ghosts reunite with their loved ones approaches, Cat must figure out how to put aside her fears for her sister's sake--and her own.