But that’s so then; this is now. The fields of genetics and neurobiology, as well as the sophistication of research methods, have upended our understanding of many things—including child development. The new science has raised new questions about how children process experience, about the malleability of characteristics previously thought of as genetic or biological “givens,” and about the potential for intervention with severely challenged children and families.
These issues are far from being simply a puzzle for philosophical pondering. Estimates are that three million-plus children in the U.S. are abused or neglected every year.[i] Additional children experience other kinds of trauma or adversity (deep poverty; exposure to domestic and community violence; parents’ substance abuse, mental illness, or incarceration; etc.). These children present huge challenges to the school system, the foster care system, the health care system, the juvenile justice system—not to mention their parents (who have often been damaged themselves). And, often, the scars are carried into adulthood where they continue to take a toll on personal life, and on society.[ii]
Our new scientific knowledge shows that genetic “blueprints” in fact are altered (for good and bad) by experience. But neither can “experience” be understood except as an ongoing, reciprocal interaction between an environment and a brain. And brains differ. Some differences are inborn, but some are not.
One of these important differences is the degree of plasticity or resilience. Some children are more reactive to changes, both positive and negative, in their environment. So, to the Nature/Nurture nexus we must add differential susceptibility (itself a product of Nature and Nurture; still with me?) Of course, central to the environment of childhood is relationships, particularly with parents and other caregivers.
Adult support (as well as the lack of it), then, is a critical component in outcomes for children. And it is where many promising programs are designed to intervene with children who have been exposed to what is sometimes termed “toxic stress.” Some of these programs address parenting skills, some work with preschool teachers, and some work with both adults and children to alter ways they experience and respond to stress.[iii]
There are limits to what can be achieved along these lines. For example, studies of severely deprived children who were institutionalized, often from birth, in Ceausescu’s Romania support the idea that the first two years are critical for certain domains of development, and that some early damage cannot be reversed.[iv]
And limits are narrower for some children than they are for others. Some children are like dandelions: given a modicum of soil, light, and water, they grow (and spread) widely, even in somewhat harsh environments; but, then, they’re dandelions. However, others are more like orchids: their needs are complex, they require a good deal of special handling, and even then they survive only in select environments. But when they do, the results are exquisite. All other things equal, exceptionally reactive children are more prone to life’s harms, but also are more responsive to life’s gifts.
So, as you remember to stop and smell the flowers this spring, be grateful for both dandelions and orchids.
Senior Research Scientist
 DeVooght, K., McCoy-Roth, M., and Freundlich, M. (2011). Young and vulnerable: Children five and under experience high maltreatment rates. Early Childhood Highlights, 2(2). Washington, DC: Child Trends. Available at http://www.childtrends.org/Files//Child_Trends-2011_04_29_ECH_YoungVulnerable.pdf
 Shonkoff, J. P., Garner, A. S., and The Committee on Psychosocial Aspects of Child and Family Health, Committee on Early Childhood, Adoption, and Dependent Care, and Section on Developmental and Behavioral Pediatrics. (2011). The lifelong effects of early childhood adversity and toxic stress. Technical Report. American Academy of Pediatrics. Retrieved from www.pediatrics.org/cgi/doi/10.1542/peds.2011-2663.
 For example, Brotman, L. M., Calzada, E., Huang, K-Y, Kingston, S., Dawson-McClure, S., Kamboukos, D., Rosenfelt, A., Schwab, A., and Petkova, E. (2011). Promoting effective parenting practices and preventing child behavior problems in school among ethnically diverse families from underserved, urban communities. Child Development, 82(1), 258-276.
 Fox, N. A. (2012). The effects of early adverse experiences on development: Lessons from the Bucharest Early Intervention Study. Presentation to the meeting, Stress, Neurodevelopment,and Programs that Promote the Well-Being of Children and Families. Office of Planning, Research, and Evaluation, U.S. Administration for Children and Families, March 13, 2012, Washington DC.