Liesl & Po by Lauren Oliver.
Orphaned Liesl is living in the attic where her stepmother has locked her when she meets a ghost. Po is clearly a child but doesn’t remember what sex it used to be and doesn’t care anymore. It’s accompanied by Bundle, an adorable little pet ghost of indeterminate species. Liesl is instantly curious, both about Po and about how it came from the Other Side, because she never got a chance to say good-bye to her very recently deceased father. Though Po is fairly certain it can’t be possible, it finds her father on the other side, and he does have a message for Liesl. At the same time, a young alchemist’s apprentice named Will is running errands for his master, as usual, going far out of his way to look for Liesl sitting in her attic window. Chronically exhausted (like me, but with a much less adorable human alarm), he accidentally leaves the box containing the most powerful magic in the world behind at one of his stops, taking instead the box of Liesl’s father’s ashes. The magic was intended for the Lady Premiere, who is most put out when it does not work as promised. Liesl, meanwhile, steals the box of what she believes to be her father’s ashes and runs away to take them to her mother’s grave. Liesl, Po, Bundle and Will all end up on the same train out of the big city, pursued by Liesl’s stepmother, the Lady Premiere, the alchemist, and the Lady Premiere’s kind-hearted but slow-witted guard, who just wants to give poor shivering Will a warm hat.
It’s all set in a smoggy grey world of indeterminate time period, somewhen between the early 20th century and now. There are trains and factories, lots of child laborers, and the sun has not shone for a very long time. Our brave children and their ghostly friends are surrounded by looming adults, nearly all of whom wish them harm. There are no powerful adults on their side, which is sad for me as a mother, but which the children seem to take for granted. Neither Will nor Liesl has much self-confidence, but together they are able to see the strengths of the other. There’s plenty of excitement, with all the mix-ups and the chases, but it has a core of sober reflection on grief. Liesl is dealing both with the fresh grief of losing her father without being able to say good-bye, and with the older grief of losing her mother years earlier. This is handled masterfully, neither whitewashing the depth of the pain nor ever making it seem that Liesl wouldn’t be able to go on with life because of it. Oliver talks in an afterward about how this book was a reaction to loss in her own life, and it shows. I never felt like Oliver was putting her characters through unnecessarily tough times just to entertain me the reader or to get them where they next needed to be. This is dealing with a tough topic in a sensitive way, all buried under an adventure and starring characters that will appeal to both boys and girls. I’d say this is best for older elementary kids. This is a beautiful tale with staying power.