Why do siblings raised in the same family environment often have wildly differing memories of childhood? How does birth order really affect life in the family? Why do siblings of the same gender tend to identify with different parents?<P>In this thoughtful and remarkable exploration of siblings of all varieties, journalist Susan Scarf Merrell brings to light some of the most painful, joyous, and confusing aspects of siblinghood as revealed in dozens of interviews.<P>No matter what kind of relationship we now have with our siblings--close or distant, loving or hostile--our histories with them exert a profound effect on our current relationships with lovers, friends, coworkers, even our own children. Utilizing the most current research and the work of psychologists, psychiatrists, and family experts, Merrell reminds us that sibling relationships are not just a blood tie, but a lifelong connection of infinite variety and fascination.