The amazing world of twins

I have recently travelled on a holiday to Vietnam with my twin sons. It was a great opportunity to enjoy nature, learn about Vietnamese culture and heritage, and equally, get to know my sons a little more. I found myself observing them with renewed curiosity. Who among them was the strategic thinker who immediately came up with a plan B when our programme was interrupted by the heavy rains? And who had the best negotiation skills when buying souvenirs at the local markets?
Psychologists have always been fascinated with twins. They share the same genes, the same home, the same upbringing, and — often — the same school environment.
In many cultures, twins are often treated as one person, starting from giving them rhyming names to dressing them in the same outfit, sometimes even calling them twins instead of using each name, this can have negative impact to the personal development of the twin causing at times sever identity crises, yet many twins are able to carve out their own identities as a way of differentiating themselves and asserting individuality.
During our trip, I noticed small but significant differences. One of my sons was the natural negotiator — he could charm his way through a delayed flight, a missed tour, or a change of plans with surprising social ease. The other was the problem solver — quick to look up alternative routes, rearrange our schedule, and keep morale high whenever things went off track. Watching them navigate unfamiliar streets, bargain in busy markets, and make sense of new cultural experiences made me appreciate how twins often complement one another like two halves of a whole.
Psychologists refer to this as “complementary differentiation” where each twin instinctively occupies a role the other does not. Sometimes one takes on the part of the leader while the other becomes the observer. In other pairs, one may be more adventurous while the other is cautious. Rather than competing, they create a natural balance that strengthens their bond and allows them to function effortlessly as a team.
The trip also reminded me of another fascinating psychological insight: twins often develop a unique communication style known as cryptophasia, or “twin talk.” Even though my sons are long past childhood, I could still see traces of this special connection. A glance was enough for them to understand each other’s moods; a short phrase, incomprehensible to outsiders, triggered laughter between them. It is as if they share an emotional shorthand built over years of shared experiences.
But perhaps the most meaningful part of this journey was realising how important it is for parents to see twins as individuals, not as a package deal. Travelling allowed me to appreciate their distinct strengths, fears and aspirations. It reminded me that even though twins may share a birthday, they do not necessarily share the same dreams.
Our short holiday gave us beautiful memories, but it also offered something deeper: a chance to understand the psychology of twins in real time and to appreciate the fact that twins have individual dreams and aspirations, and we should encourage them to complement each other rather than compete with one another.