Stress is a universal part of life, but for babies and young children, the way stress is experienced – and the support they receive – can shape lifelong health. Parents and caregivers are not just helpers in this process; they are the most powerful protective factor a child has. Understanding how stress works gives families the tools to nurture resilience, prevent harm, and support healthy development from the very beginning.
Why Stress Matters for Lifelong Health
Decades of research show that early experiences influence the architecture of the developing brain. The Adverse Childhood Experiences (ACE) Study revealed that individuals exposed to chronic or severe stress in childhood are significantly more likely to develop heart disease, obesity, depression, and substance use disorders later in life (Felitti et al., 1998).
- Adults with an ACE score of 5-6 are twice as likely to develop cardiovascular disease or substance use disorders.
- Adults with an ACE score of 7-8 are three times more likely to experience major health problems compared to those with lower ACE scores.
This research underscores a powerful truth: early stress is not just an emotional experience – it is a biological one. And the presence of caring adults can dramatically change a child’s trajectory.
How Stress Shows Up in Babies - and in Caregivers
Babies communicate stress through crying, fussing, arching, or withdrawing. These signals are not misbehavior; they are requests for connection. When caregivers respond with warmth and presence, the child’s stress response settles and the brain learns safety.
Caregivers, however, experience stress too. Hearing a baby cry can activate an adult’s own stress response, raising cortisol levels and making it harder to stay calm. This is normal. What matters is having support, taking breaks, and remembering that your regulation helps your child regulate.
Chronic stress without support can disrupt brain development in both children and adults. Cortisol – a hormone essential for survival – becomes harmful when elevated for long periods (Shonkoff et al., 2012). This is why preventative care and early support are far more effective than intervention after harm has occurred.
The Science of Brain Development
Healthy brain architecture begins before birth and is built through serve and return interactions – the back and forth exchanges between a child and caregiver that shape emotional, cognitive, and social development (Center on the Developing Child, 2015).
Key principles parents and caregivers should know:
- Development is interactive, not predetermined by genes.
- Multiple caregivers matter – children benefit from responsive relationships beyond their parents.
- The first three years are foundational, but the brain remains adaptable throughout childhood.
- Severe neglect can be as harmful as physical abuse, because it deprives the brain of essential stimulation.
- Removing a child from danger is not enough – healing requires consistent, nurturing relationships.
- Resilience grows through relationships, not through independence or “toughing it out.”
Types of Stress: Positive, Tolerable, and Toxic
Not all stress is harmful. Understanding the three types helps caregivers respond effectively.
Positive Stress
Short term stress that helps children learn and grow — like trying something new or meeting a challenge. With supportive adults, children gain confidence and coping skills. Cortisol rises briefly and returns to baseline.
Tolerable Stress
Triggered by difficult events such as the loss of a loved one, a natural disaster, or a serious illness. With strong caregiver support, the child’s stress response can return to normal. These experiences can build resilience when handled with care.
Toxic Stress
Occurs when a child experiences strong, frequent, or prolonged adversity without supportive relationships. Examples include chronic neglect, caregiver mental illness, substance use, or exposure to violence.
Toxic stress can:
- Disrupt brain architecture
- Kill neurons in the hippocampus
- Alter emotional regulation
- Increase lifelong risk for anxiety, depression, and chronic disease (Shonkoff et al., 2012)
Children exposed to trauma may show:
- Nightmares or intrusive memories
- Withdrawal or numbness
- Irritability or anger
- Hypervigilance
- Difficulty concentrating
- Emotional “shutdown”
Even witnessing violence — such as intimate partner violence — can trigger traumatic stress. Infants and toddlers who lack responsive care show cortisol patterns similar to children who have been physically abused (National Scientific Council on the Developing Child, 2014). Poverty also increases the likelihood of toxic stress due to instability and caregiver strain.
Preventing Toxic Stress: What Families Can Do
The most powerful buffer against toxic stress is a stable, nurturing relationship with at least one caring adult.
Parents and caregivers can protect children by:
- Responding consistently to their cues
- Creating predictable routines
- Practicing co regulation (breathing together, rocking, holding)
- Seeking support when overwhelmed
- Building a network of trusted caregivers
Children are deeply affected by what they see, hear, and feel. When caregivers receive support, children benefit too.
Community Resources for Support
These organizations offer guidance, connection, and healing for families:
- Mary’s Center – prenatal and family health support
- Kate’s Club – grief support for children
- Mothers and Babies Program – evidence based maternal mental health support
- NW Children’s Foundation – trauma informed family resources
- Modern Collective Care – community centered postpartum and caregiver support
The Center on the Developing Child has pioneered an Early Childhood Development (ECD) framework that strengthens the foundations of healthy development. Until these models are widely adopted across healthcare and childcare systems, early childhood outcomes – and societal health – will continue to be at risk.
References
Center on the Developing Child at Harvard University. (2015). The science of early childhood development. https://developingchild.harvard.edu
Center on the Developing Child at Harvard University. (2023). Toxic stress. https://developingchild.harvard.edu
Felitti, V. J., Anda, R. F., Nordenberg, D., Williamson, D. F., Spitz, A. M., Edwards, V., Koss, M. P., & Marks, J. S. (1998). Relationship of childhood abuse and household dysfunction to many of the leading causes of death in adults: The Adverse Childhood Experiences (ACE) Study. American Journal of Preventive Medicine, 14(4), 245–258.
National Scientific Council on the Developing Child. (2014). Excessive stress disrupts the architecture of the developing brain (Working Paper No. 3). Center on the Developing Child at Harvard University.
Shonkoff, J. P., Garner, A. S., Siegel, B. S., Dobbins, M. I., Earls, M. F., McGuinn, L., Pascoe, J., & Wood, D. L. (2012). The lifelong effects of early childhood adversity and toxic stress. Pediatrics, 129(1), e232–e246.