A sister is like yourself in a different movie, a movie that stars you in a different life.

Sister relationships span a huge range, from best friends to worst enemies. From 'I adore her; I talk to her five times a day' to 'I decided to cut her out of my life.' For most women, it's in between.

A sister is someone who owns part of what you own: a house, perhaps, or a less tangible legacy, like memories of your childhood and the experience of your family.

Life is a matter of dealing with other people, in little matters and cataclysmic ones, and that means a series of conversations.

American popular culture, like individuals in daily life, tends to either romanticize or demonize mothers. We ricochet between 'Everything I ever accomplished I owe to my mother' and 'Every problem I have in my life is my mother's fault.'

In a world of status, independence is key, because a primary means of establishing status is to tell others what to do, and taking orders is a marker of low status. Though all humans need both intimacy and independence, women tend to focus on the first and men on the second. It is as if their lifeblood ran in different directions.