Scientists have discovered something remarkable: during pregnancy, cells pass between a mother and her baby, and researchers have found that some of these cells remain in the body for decades rather than disappearing after birth. The science of microchimerism suggests that the people who shape us never completely leave us, biologically or emotionally. That idea has as much to say about psychology and legacy as it does about biology.
What Is Microchimerism?
The phenomenon is called microchimerism. The name comes from Greek mythology and refers to the presence of a small number of cells that originated from another person. Researchers have found maternal cells in adult children and fetal cells in mothers many years after pregnancy. The science is fascinating, and the implications are even more so. As researchers continue to study microchimerism, many of us find ourselves drawn not only to the biology but to the deeper question it raises: what does it mean to carry pieces of another person throughout our lives?
Are We More Connected to Each Other Than We Realize?
Most of us think of ourselves as independent individuals, yet from the moment we are born, our lives are shaped by countless influences. We carry family stories, traditions, and values. We carry lessons learned through love, hardship, success, disappointment, resilience, and recovery. Microchimerism suggests that some of us may literally carry tiny physical traces of those who came before us. Whether those cells remain active or simply persist as biological remnants is still being studied, but the idea itself is powerful: perhaps none of us travel through life alone.
How Does Being “Shaped” by Others Show Up Psychologically?
As a psychologist, I have spent much of my career helping people understand how their past influences their present. Our childhood experiences matter. Our relationships matter. The people who encouraged us matter, and so do the people who hurt us and the people who believed in us. Even decades later, those experiences continue to shape how we think, feel, and respond to the world.
Microchimerism offers a fascinating biological parallel to something psychologists have long understood: the people who shape us never completely leave us. Their influence continues long after specific moments have passed. We may not consciously think about those influences every day, but they remain part of our story.
Is Aging About Starting Over, or Something Else?
One of the messages I return to often in 77 and Still Standing is that aging is not about becoming someone new. It is about becoming more fully yourself. Popular culture often encourages reinvention, but many of us do not need reinvention. We need recalibration: recognizing the strengths, wisdom, resilience, and experiences we have already accumulated. Our history is not a burden. It is a foundation. Like the roots of a tree, much of what sustains us lies beneath the surface. You may not see your roots every day, but they are there, supporting you, steadying you, and helping you continue to grow.
What Do Your Roots Actually Represent?
The image accompanying this article shows a tree with roots labeled:
- Love
- Family
- Wisdom
- Lessons
- Challenges
- Friendships
- Strength
Those roots represent far more than biology. They represent the people and experiences that have shaped us. Some roots were formed through joy, others through loss. Some came from triumph, others from adversity. Yet all of them contribute to who we are today. The older I get, the more convinced I become that resilience is not something we suddenly acquire. It develops over time, growing from the roots we have spent a lifetime building.
Does Our Influence on Others Continue After We’re Gone?
Perhaps the most beautiful aspect of microchimerism is the possibility that our connection to others extends across generations. Researchers are even exploring whether cells may pass from grandmother to mother to child. Whether future studies confirm every aspect of that possibility remains to be seen, but the larger truth is already evident: we influence one another across generations, decades, and families. The love we give, the lessons we teach, the values we model, and the encouragement we offer do not end with us. They travel forward, carried by children, grandchildren, friends, students, neighbors, and countless others whose lives we touch.
They shape us. They stay with us. They travel forward through us. And perhaps that is one of the greatest lessons of aging: your roots run deep, your story continues, and there is still more to be written and carried forward.
