When twins marry or become seriously involved with a partner, interpersonal problems involving their co-twin are commonly triggered. For example, George won't attend his twin brother Bill’s wedding because he thinks Bill’s fiancé, Mary, is too materialistic. Disappointment, jealousy, and too many expectations concerning the twins and the new family are hard problems to understand and resolve.

These emotional schisms can last a long time and they can be difficult to contend with on a personal level as well, because family outsiders often do not believe that twins fight and don't get along. Smoothing out or avoiding family misunderstandings is a problem for many families with twins that makes all kinds of holidays and “family events” very stressful. Confronting problems can be almost impossible, in my experience. While the parents of twins often try to get to the bottom of the problem, success is hard to achieve. Problems are usually based on favoritism created in early life. Favoritism leads to jealousy. Favoritism really poisons the family well.

Generally speaking, the magnitude of the problem to be solved, which is made worse over time, along with jealousy (sometimes open jealousy but usually with some degree of secrecy or buried feelings) and the need for everyone to have their own way and be in control, are the motivators of family fighting when twins are involved.........

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