The second book in the Ender series by Orson Scott Card is entitled Speaker for the Dead. This book is a continuation of the story begun with Ender's Game. There we met Andrew "Ender" Wiggin who was bred to be a great military leader to help humanity fend off an alien invasion. Ultimately Ender grew into the role that our military had hoped for, and by the age of 12 he had completely eradicated the so-called "Bugger" threat. The story ended when we came to understood that Ender had no knowledge that he was utterly destroying an intelligent, compassionate, and highly advanced civilization. In fact, humanity acted as it did because it felt a threat to its continued existence but had very little knowledge on who its perceived enemy was. As a result of this, Ender and his sister Valentine, traveled from world to world. Ender grew into a role called a "speaker for the dead", whose central purpose was initially to educate humanity on the Bugger race and how we had completely misunderstood their intentions. Eventually Ender became a speaker for whoever called upon him. His role was not to deliver a praise-filled eulogy covered with dull platitudes, but to deliver the truth about who a person was in contrast to who they were perceived to be.
This part of the story is completely different than Ender's Game with essentially a completely new cast of characters. The story mostly takes place on a distant world called Lusitania, which was set up as a Catholic colony. On this world is a sentient group of creatures referred to as "piggies". Strict scientific protocols have been established for the humans to interact with the piggies and learn all they can about them without poisoning their development or evolution. When two of the scientists of the observing team are killed by the piggies, humanity seems once again all too eager to jump to conclusions about the alien's intentions. This is the moment that Ender arrives on the scene and forms a bridge between humanity and the piggies, and the two sides come to understand and appreciate each other for who they are. However, the human leadership observing Lusitania from the surrounding worlds has already set into motion a plan to remove all humans from Lusitania in the firm belief that our presence has set the piggies up to threaten humanity. Will another alien race be exterminated by bias and misunderstanding? These questions will be answered in the third book in the series, Xenocide.