Having a sister is like having a best friend you can’t get rid of. You know whatever you do, they’ll still be there. –Amy Li

My middle sister and I fought like wildcats when we were growing up. One of my most vivid childhood memories is of being forcibly separated during an argument and banished to sit together on the living room couch with orders not to get up until we could get along. I huddled against one arm and resigned myself to living on that two-foot square cushion for the next eleven years, when I would turn eighteen and could get my own apartment. After an eternity, Mom entered the room to mediate. “Girls,” she said, “you are sisters. There will never be another person in the world more closely related to you than your sister. So you’d better learn to get along, because someday one of you might need a kidney.” Not, perhaps, the most convincing argument for reconciliation ever presented, but it worked. For the moment, anyway.

A woman has many relationships in her life, but the bond between sisters is unique. There is the biological link, but the connection goes beyond that. Sisters enjoy a shared past. They experienced many of the same events that molded their personalities, and therefore they understand one another in a way no one else can. They speak the same shorthand. If one of my sisters says, “I know! Let’s put on a show!” we all laugh, because we remember the first time one of us said that, and the resulting spectacle that has become family legend.

Sisters “get” each other without having to go into all the background. When I’ve had an argument with my husband, I can call my sisters and say, “He doesn’t want a puppy. I think I may divorce him.” My sisters understand my reaction immediately, because they remember witnessing our parents’ argument over the same subject. They can talk me down from the ledge, and away from the divorce attorneys. And they will do this even if I call them at three o’clock in the morning, with only a minimum amount of grumbling about the loss of sleep.

Psychologist Marcia Millman, author of The Perfect Sister, said during an interview, “I think sisters can help repair the injuries of childhood.” That’s certainly been true in my family. Whenever we get together, our husbands cover yawns and eventually slip away to the other room to watch a ballgame while we rehash events of our childhood, and discuss how they have impacted us as adults. Often I come away with a new perspective and a better attitude, so gatherings with my sisters are sort of like group therapy sessions. Only less expensive.

While it’s true that we share a common past, even sisters experience different events while growing up in the same household. I like to remind both of my sisters that, being the oldest, I blazed the trail for them. They both got their ears pierced sooner than I did, and wore lipstick, and shaved their legs. They were both allowed to date at an earlier age than I was, and stay out later. There are ten years between my youngest sister and me, so by the time she became a teenager, I had successfully driven our parents into a state of exhausted stupor, and she got to do pretty much whatever she wanted. (Which I still think is totally unfair, but that’s the way it is in most families, I’ve learned.) I think she owes me big-time.

My sisters and I do still have the occasional conflict. Author Linda Sunshine said, “If you don’t understand how a woman could both love her sister dearly and want to wring her neck at the same time, then you were probably an only child.” Our arguments don’t become physical anymore (we all understand the importance of good hair now, so we are no longer tempted to grab a handful), but these days, being at odds with one of my sisters is far more painful than our childhood brawls.

Several years ago, my middle sister and I had a disagreement and didn’t speak to each other for a few days. I was miserable without her, but we both stubbornly refused to back down. While cooking dinner one evening, I dropped a glass measuring cup she had given me, and it shattered. When it did, my stubbornness broke into a million pieces. My husband brought the phone to me where I sat sobbing on the floor, surrounded by shards of glass, and said sternly, “Call your sister.” Never has a reunion been so sweet.

Someone once said that relationships between siblings are the most long-lasting and influential of all. My sisters have been a part of my life longer than my husband or my children, and they will be part of my life even after our parents are gone. They know me, and understand me, and they like me anyway. They’re one of the best blessings God has given me. And as Mom said, if I ever do need a kidney, I know who to call.