I am often reading between 3 and 5 books at the same time, and occasionally there’s a theme that might not be remarkable in one book… but when I see it in three books, I take notice.
In the Shadow of Blackbirds by Cat Winters included among its characters a set of brothers, one of whom is “killed in the war” (the war being World War I). Stephen’s ghost returns to haunt the narrator and resolve some things that happened between the brothers.
Shortly after reading this one, I read Cuckoo Song by Frances Hardinge, which took place shortly after the end of World War I, and featured another brother killed in the war. Sebastian “returns” via letters that are deposited in a desk, and haunts his fiancee as well.
Then I started reading an advanced copy of The Bone Witch by Rin Chupeco, and yet another dead brother showed up. No World War I this time, as the story takes place in a fantasy universe, but Fox dies in the war, and his sister brings him back from the dead.
Coincidence? Maybe. In any case, very strange that three books I read within a month’s time had brothers who died in a war and then returned from the dead.