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Understanding Twins

Why Have My Teenage Twins Started Fighting Endlessly?

Understanding the difficulties of twin separation in adolescence.

Key points

  • Twins' separation from one another is healthy and necessary for the development of their individuality.
  • Twins who have a sense of themselves as individuals may argue about their differences.
  • Acceptance of non-confrontational fighting and staying neutral are the only reasonable approaches.

The teenage years are a time for separation from the family. Twin teenagers can react even more strongly than non-twins because they are working on separating from their parents and from each other.

Clearly, there are many varieties and manifestations of separation anxiety in teenage twins. The quality of parenting and the interdependence or independence between twins will determine the depth and extent of turmoil between the twins, and the twins and their parents.

When twins are too close, observable separation anxiety may not take place, because separation anxiety is too overwhelming. In other words, twins who are really afraid to separate try to ignore their need for independence. They have to always be together.

In contrast, twins who have a sense of themselves as individuals may argue about their differences and even demonstrate “fireworks” behavior—yelling and name-calling when they are angry or feel misunderstood by each other. When one twin is favored, hostility towards the non-favored twin is acted out.

Unseen and visible anger at parents and between twins are commonplace events, to the horror and confusion of parents, who call me asking:

  • “Why do my twins hate each other? They were as close as shadows.”
  • “Why are my twins ignoring each other or leaving one another out in social situations?”
  • “One of my twins called and asked me to disown his twin brother.”

The courage to separate from one another in the teens is healthy and necessary for the development of individuality, but it is an extremely painful struggle for the twins and their parents. Another "normal teenage argument" related to separation anxiety is, “Who is a non-shared friend?” or “To which twin does the new friendship belong?”

“Is he my friend or is he your friend?” is a very predictable quandary in the teenage years, though it is much less of an issue in childhood. I say bravo to twins and families who understand the importance of non-shared friends for twins.

The Difficulty of Accepting That Twins Are Different People

Specifically, a strong and heartfelt realization that there are long-standing similarities and objective differences between the twin pair can be hard for preteen and teenage twins to process. For example, I remember how seriously my sister teased and even ridiculed me for having a boyfriend who often displaced her importance and connection to me. As well, I will not forget how hard she tried to convince me to be an English major instead of a History major at Cal Berkeley. Our differences in our educational choices and our friendships turned into arguments that symbolized how we were different. Less-serious arguments or just “friction” about who has the most attractive boyfriend, the best style, grades, or athletic abilities also reflect/reinforce to twins that there are real differences in their friendships, interests, and abilities.

More often than not, being different from your twin is very exciting and an accomplishment. Unfortunately, at the same time, the loss of your perfect twin mirror is hard to come to terms with in personal and professional experiences. Non-twins have very different expectations for relationships than twins. Non-twins think that twins are demanding, and twins feel that non-twins are very disappointing.

Twins are born with the affirmation that their twin gives to them by being like them, next to them, and understanding them on a deep level. Twins want and even need the mirroring aspects of their twin identity. Fortunately, twins also want to be their own special person.

Teenage Fighting

Fighting over being different and not being the "same" occurs in the teen years, even though it wasn't noticeable or as strongly felt in childhood. In other words, twins are self-conscious and frustrated by differences as teens.

The drama created by adolescent separation is very real and very hard to deal with if you want to make your children’s fighting less intense. Acceptance of non-confrontational fighting and staying neutral are the only reasonable approaches. Physical and verbal abuse should not be tolerated, and the consequences of out-of-control behavior should be explained and implemented.

When anger subsides, ask questions about what is causing the fight. Avoid expressing your curiosity in the middle of an argument.

In the teenage years, anger and fighting are easily triggered by new friends who enter the twin social circle. Outsiders, no matter how accepting, can inspire new types of distance between twins, such as not-sharing experiences and clothes, games, and special events.

Distance is normal and healthy as it is the beginning of the journey to a very separate identity, which is necessary for maturity and happiness. Developing a matter-of-fact state of mind that fighting is age-appropriate for teenagers seems to help everyone. If you forget this point, remind yourself how your child's physical appearance has changed and how much stronger their intellectual development has become.

Try to keep in mind that separation anxiety is a part of individual development. Twins' anger at one other is not indicative of “bad” things ahead. It is very common for parents to think the worst, which does not help. The fact is that twins suffer from separation anxiety, which they act out with each other.

Advice for Weary Parents

  1. When your twins are fighting, no matter their age, separate them.
  2. Give your twins separate school, social, and emotional experiences.
  3. Know how your children are different and encourage and praise their differences.
  4. Plan to spend time alone with each twin every week.
  5. Talk to your twins about separation issues, as this will normalize their problems and give some calm to your home environment.
More from Barbara Klein Ph.D., Ed.D.
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