McFig & McFly: A Tale of Jealousy, Revenge, and Death (with a Happy Ending) by Henrik Drescher
McFig lives with his daughter, Rosie, in a lovely little cottage far away from anywhere big and important. One day, McFly and his son, Anton, buy the land next door. At first McFig and McFly hit it off big-time and build McFly a cottage modeled exactly after McFig’s house. But then the two start to add things onto their houses — a medieval tower, a second-story playroom — and soon McFig and McFly are in a lifelong competition to be bigger and better than each other. Where will all their obsessive one-upmanship end?