"It was hard to convince him that this would be the best way, that a Pureblood heir was what he needed instead of a true heir that would only be a half-blood. Consider this payback for all the wretched things you did to me in school, because what better punishment than forcing you to give me a child that you may or may not live to see grow up and completely destroy the world. Your only child who will never know you as a father, but as a soldier in his father's army. Yes, it was hard to convince the Dark Lord that this would be the best way, but it wasn't hard to convince him that you would be the best choice."