The deep interconnection of psychological identity between twins is real. Unlike single-born infants and toddlers, shared identity is inevitable and normal. Some aspect of a twin’s sense of self is actually shared. A twin has an identity as a twin and an identity as an individual. Twins are closer than brothers and sisters because they share an identity based on early life experiences and the reaction of others. Ego boundary confusion is understandable and predictable, although I really think the ego boundary lingo is not accurate for twins. For example, if a pair of twins makes decisions together as young children, is this abnormal? Even when they are just playing together and sharing?

When does sharing become pathological?

When is fighting too much fighting?

“How do I do something new without my twin?” is a difficult issue that is hard to work through as well. Being alone becomes a critical problem as twins grow into adulthood.

Unfortunately, it is an easy and often-made mistake for teachers and therapists to glibly say, “This is just an ego boundary problem. If you could just set up realistic rules and follow through on them you would not have problems with your twin.”

I have been told this myself far too many times. From my personal and professional experiences, I know it is easier to corral wild horses than to set up ego boundaries for twins. Certainly, parents, twins themselves, and therapists should attempt to acknowledge and hold on to individual differences with the highest regard for empathy, truth, and integrity. Individuality is a necessary part of healthy twins’ development. Believing that you can actually dictate individuality in twins is short-sighted, futile, and grandiose. And clearly, some identity that is shared between twins is intractable and life-sustaining.