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Understanding Twins

Loss of a Twin

Loss of a twin is a devastating life event.

The Twinless Twins Support Group International (TTSGI) was founded in 1984, by Dr. Raymond Brandt. Its annual conventions allow dozens of twins to share their life stories with those who fully understand the nature and level of their grief. Many TTSGI members have participated in the ongoing Fullerton Twin Loss Study, research that began at the University of Minnesota in 1985. Some twins from the Australian Twin Register have also taken part.

I attended the July 2009 Twinless Twins Convention, held in Denver Colorado. This meeting drew dozens of bereaved twins and some parents of twins together for a weekend of important and memorable moments. Highlights from two events (the keynote address and twin testimonials) follow a selected sampling of research findings on twin loss. Note that the original article and references will be published in the next issue of Twin Research and Human Genetics.

Two key findings have emerged from the extant research on twin loss. The first is that identical twins experience the loss somewhat more intensely than fraternal twins, although there is considerable overlap—the loss experience may be just as devastating for some fraternals. There is also evidence of less grief reduction over time for identical than fraternal twins, on average. The second finding is that the loss of a twin is associated with greater grief than the loss of any other relative, with the exception of a spouse.

This make sense in evolutionary terms—in the absence of a partner, one cannot transmit genes to future generations. At the proximal level, spouses are the people chosen to be lifelong companions. Interestingly, grief associated with spouse loss did not differ from grief associated with twin loss. Comparing the effects of twin loss versus spouse loss between surviving MZ and DZ twins would be revealing; however, my own sample of nearly 700 bereaved twins does not include sufficient numbers to support such an analysis. In addition, very few twins (fortunately!) have lost children, also precluding twin group analyses of such data.

Loss of a twin either before, or shortly after, birth can profoundly affect surviving twins. Biographies of well-known figures, such as science fiction author Philip K. Dick and rock n’ roll star Elvis Presley include references to the missing twin in childhood and adulthood. Joan Woodward has studied such cases, but research in this area is clearly wanting. A timely issue concerns the emotional responses of adult individuals whose co-twins were selectively terminated, following the successful implantation of multiple embryos. I am unaware that such research has been done.

Suicide survivors constitute a special subgroup of surviving twins. They are a valuable research group because they enhance understanding of the nature and origins of suicidal behavior. My own research, in conjunction with Dr. Alec Roy, has indicated a higher frequency of suicide attempts among identical than fraternal twins whose co-twins had suicided. They also found that suicide attempts occurred with very low frequency among both types of twins whose co-twins’ death were non-suicides. These results are consistent with genetic effects on suicidal behavior.

Danish investigators reported a reduction in suicide among both identical and fraternal twins, relative to non-twins. The interpretation was that twins provide social support for one another, offsetting any risk. Another Danish team) found that survival is improved by having a spouse, friends, and a co-twin. Contact frequency was a significant factor in the survival of women and MZ twins.

Finally, the coping process of some twin suicide survivors can be complicated because they cannot express anger at a person or event for causing their twin’s death. This reaction was expressed by several twin suicide survivors at this year’s Twinless Twins convention.

The first address of the morning was by New York City clinical psychologist Mary Morgan. She was ideally qualified to do this, given her professional background and the fact that she lost her twin brother at the age of twenty-one. She mentioned the immediate connection she felt with the group when she first joined.

Several key themes were touched upon in her talk. One was the extreme loneliness that twins feel when they lose their co-twin. Everyday reminders (e.g., a song or a smell) can reawaken the fact that the twin is no longer present. Another theme was the uniqueness of each person’s recovery process. People cope with their loss in individual ways and according to individual timetables. A final theme was the lack of understanding that some family members may unknowingly display toward bereaved twins. The process of recovery may take longer for twins than for non-twin relatives who can become impatient with twins’ enduring grief. All these themes have emerged from the Twin Loss Surveys completed for the Fullerton Twin Loss Study.

Mary Morgan should be applauded for her efforts on behalf of the twin survivors of the World Trade Tower attack. She organized a support group for several of the New York City twins for many months in the aftermath of that tragic event. Additional information about her work can be found at twinlesstwins. A biographical sketch of one such survivor is included in my book, Indivisible by Two: Lives of Extraordinary Twins.

The second part of the day was dedicated to twin testimonials. Twins were invited to describe the circumstances of their loss, its effects on their life, their methods for coping, and their fondest memories of their twins. These sessions were extremely moving and gave depth and substance to the data files that others and I have amassed over the years. Each life story was a different take on the emotional difficulties and complexities that bereaved twins face. Teenagers mourned the fact that they would not experience this crucial life stage with their twin. Young adults worried about the well-being of their nieces and nephews (their co-twins' children). Older twins, even those whose twins had died many years before, emphasized the unreality of their loss. Many told me privately that one never fully gets over the loss of a twin, which may explain why some twins return to the convention year after year. It was observed (ironically) that TTSGI’s members are highly dedicated to the organization, even while they would prefer to be non-members.

Twin researchers are in the fortunate position of producing findings that are meaningful at both theoretical and applied levels. Closer personal contact between researchers and twins has enormous benefits for everyone. It provides twins with information and guidance and offers researchers ideas and topics for future study.

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