In Zia, Zia and her brother exclusively discuss going to the island to save Karana, but no one ever mentions Ramo. While the reader knows he's long dead, Karana's sister would have had no way of knowing this, and therefore neither does Zia. Zia should be thinking that both Karana and Ramo are possibly alive, but instead neither she nor anyone else mentions Ramo at all. It seems like this was a choice that was made for narrative convenience — readers would have all but forgotten about Ramo, so focus on the character they care about — but it fails the logic test in-universe.
