Dear Tanya,

I am 35 years old and have a sister two years younger than me. We are of about equal academic ability and attractiveness (physically and in terms of personality). We have both suffered from depression and various health problems over the years. She has been successful in her career while I have married and have a loving partner but because of frequent illness have had an undistinguished work record. I am very proud of her success and have told her so. Three years ago our mother died and, although I was ill, I phoned her several times a week and was very concerned about her mental state. She took this very much for granted. In the past six months, we have both been ill again. I phoned, e-mailed, and tried to cheer her up. Again she seemed to take this for granted because I have a relationship and she doesn't, although she has many good friends. Now she's feeling better and never bothers to phone or show any interest in how I am (I have had ME for the past ten years, although it was diagnosed only a year ago). I e-mailed about a week ago to point this out and she has not replied. Her attitude seems to be that I am good enough to support her when she is down but as soon as she's feeling better I am not worth her time. I feel hurt and disappointed and feel that she is being mean spirited. It's as if, because I have a partner, she doesn't see why I should have any support from her. She seems to resent anything good in my life and to regard herself as more deserving of happiness.

Helen

This is an interesting time for me to read your e-mail because sisterhood is very much on my mind - my only sibling, my sister Katrina, is about to get married. Katrina is 15 months younger than me and we both readily acknowledge that our relationship over the years has taken many emotional twists and turns, some intensely positive and others intensely not so.

Katrina and I are bound to each other by a profound sense of shared significant life history. She was at the birth of my daughter and she was the person who told me that our father had died. I consider her to be my closest friend and confidante and one of the most incredible women I know. If she wasn't my sister, I would want her to be my friend. But it wasn't always like that for me or for Katrina. We found our relationship independent of family, as adults, when we were both ready.

Sibling rivalry is a subject that I am often asked about in the context of younger children by desperate and exhausted parents. Most rivalries between siblings still living in the family unit are developmentally normal. They represent the relationship context within which many key social and emotional experiences can be played out with those to whom we are closest genetically and socially. The sibling bond is complex, changeable and charged with the most intense emotions. This relationship is built around an interaction of genes, parental treatment, life events, and generational, ethnic and cultural factors. In adulthood, sibling rivalry becomes more problematic as years of complex and entrenched experiences and behaviours are laid down. Patterns of interaction that seemed “developmentally normal” in little ones become trickier as old memories are ignited and because as adults we are less able to draw lines in the sand and move on in the way that children can.

Research indicates that the patterns of sibling interaction are laid down at very young ages - even at the age of one year, siblings are seen to be profoundly affected by their mother's interaction with other siblings. Most 18-month-old children have an awareness of and respond to perceived differences in parental affection with other siblings - hostility and conflict builds and fights are played out to set up siblings and get parental attention.

It might be useful, Helen, to look at what might have been established in your early relationship with your sister, particularly in regard to your parents. Is what is being acted out in your thirties a product of envy and resentments from early childhood?

What strikes me is that you seem to compare yourself and your sister as equals in terms of looks, intellect, personality and mental health. However, while you are sisters, you are also individuals with, I'm sure, more differences than similarities and different perspectives on life and relationships. You seem to measure yourselves as equals, and even the mismatch that exists between you in her career and your marriage, seems to be seen by you as one balancing against the other. Part of the problem you experience is to do with your expectations of your sister and how she should behave in your relationship that are built around a notion of “I do for you, therefore you do for me”. I have some sympathy with your position but I wonder whether your neediness is also part of the problem - the more you give, the more she withdraws.

Sibling relationships can change dramatically over the years and important life events in adulthood can bring siblings closer together or split them further apart - and this includes marriage. You are married and your sister isn't and this could set up an uncomfortable dynamic, particularly if there are issues between a sibling and a brother/sister-in-law.

The author and poet Maya Angelou once said: “I don't believe the accident of birth makes people sisters or brothers. It makes them siblings. Gives them mutuality of parentage. Sisterhood and brotherhood is a condition people have to work at.”

My feeling, Helen, is that it would help you if you looked at your relationship with your sister not as a given but as a possibility that will take work from both of you (if that's what you both want) and a good deal of compromise on both sides. This can begin only when you know each other as individuals and not as an extension of each other.

One of the differences between the sibling relationship and a close friendship is the lack of boundaries. There are things we would say to a brother and sister in a rage that we would never say to a friend. I wonder whether it would help if you adjusted yourself in this relationship and imposed some boundaries for yourself, including attempting not to take your sister's every action (or lack of) as a personal slight. Her behaviour may reflect issues that are nothing to do with you. Find support from others you are close to in your life and let go of a build-up of grudges and a memorised catalogue of her not being good enough.

Maybe your sister will respond to a different approach from you and just enjoy a day out together if the agenda is having fun with no intense conversations. Maybe this isn't your time to be close but that time will come.

At this time the only person you can change in this relationship is yourself and I suggest that the best thing you can do is to expect less and not do as much of the running. Your sister may surprise you and give more.

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