To be sure, some brothers and sisters have relationships that are easy. But oh, some relationships can be fraught. Confusing, too: How can two people share the same parents and turn out to be entirely different? Marie Brenner's brother, Carl-yin to her yang, red state to her blue state-lived in Texas and in the apple country of Washington state, cultivating his orchards, polishing his guns, and (no doubt causing their grandfather Isidor to turn in...