The Language of Ghosts by Heather Fawcett

My name is Noa, and my brother Julian should have been the one promoted to become the new king. He's able to speak all nine languages to create the most powerful dark magic in the kingdom, but Xavier was able to turn many other mages against him. Now, we find ourselves sailing across the seas, slowly retaking islands from Xavier's rule. I'm concerned about some of Julian's decisions, and I fear he'll become the evil mage Xavier's been talking about. I wish he'd listen to more of my ideas and think things through before acting. Maybe he would if I was also a mage. He prefers to attack his problems with magic without worrying about anyone he might hurt. Xavier has sent his mages and navy to find us on our floating island, and it's only a matter of time before we're found. I'm afraid for what will happen when that day comes. 

I kept waiting for the ghosts promised in the book's title, and they finally arrived toward the middle of the plot. I expected ghosts to be the main part of the story, but death might be a better word in the book's title. As expected, Noa had an unknown magical ability that opened up new ways for her to get into trouble. It really bugged her when she thought only her brother and little sister had abilities. Julian was the most interesting character, as it was never quite clear if he was an evil, heartless mage. He easily executed some characters, but Noa was doing her best to nurture some humanity in him. Julian said she gave good advice, but she was frustrated that he continued to make impulsive decisions. It was funny that she also made rash decisions, because she thought she knew what was best. Her little sister Mite, and a sea monster guarding the island were entertaining additions to the story. Mite was frustrated about being ignored or forgotten, and her magical powers were unpredictable. She could blow things up at any time. The sea monster was controlled by Julian, and she didn't like it one bit. She enjoyed attacking and eating invaders, but she would equally savor the taste of Julian or his followers. Overall, I recommend you give this book a shot, as it's also a nominee for a 2020 Cybils Award.