Not Just a Phase: How Child Mental Health Develops Over Time
Why early symptoms may resolve, persist, or change and what that means for support.
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One parent might say, “My kindergartner cries every morning before school—will they always be anxious?” Another wonders, “My 8-year-old is constantly getting in trouble. Should I be worried about what this means for the future?”
These are common questions from parents and it is important to know that mental health in childhood doesn’t follow a straight line. Some symptoms resolve, others persist, and some evolve into entirely new challenges.
That’s where developmental psychopathology comes in. It’s a research lens that helps us understand how mental health unfolds over time—how anxiety, emotion dysregulation, or behavior problems in childhood can change, stabilize, or shift in adolescence and beyond. It teaches us to look at patterns, not just moments—and that’s good news for supporting kids as they grow.
To make sense of the research, here are a few key terms I’ll use throughout—no jargon, just helpful language to describe how symptoms unfold over time.
Key Concepts
Developmental Psychopathology (DP): A scientific lens for understanding how typical and atypical development interact. It focuses on how mental health challenges emerge, change, or persist across time and context.
Trajectories: Symptom patterns over time, such as increasing, decreasing, or stable.
How symptoms can shift or stay the same: Some children’s challenges stick around in the same form (like early anxiety continuing into adolescence). Others may change over time (like preschool behavior problems.
Research Spotlight: Longitudinal Patterns
Childhood anxiety/depression trajectories: A Dutch cohort study found four symptom patterns from preschool to middle childhood (low, increasing, decreasing, and preschool-limited). Each pattern was linked to later social and academic outcomes. (de Lijster et al., 2019).
Mental health during the pandemic: The COPSY study in Germany showed that most kids maintained low symptom levels, but 10–18% followed rising or fluctuating paths. These shifts were associated with specific risk and protective factors. (Kaman et al., 2024).
Adolescent trajectories predict adult outcomes: Longitudinal research confirms that adolescent patterns of internalizing and externalizing symptoms often predict early adult mental health and functioning, independent of earlier childhood risk. (Cyr et al., 2020; Katsantonis, 2024; Oerlemans, et al., 2020).
Early emotional and behavioral difficulties predict adolescent health:
A UK study following over 11,000 children from age 3 to 17 (Black et al., 2023) identified 4 common developmental pathways:No significant difficulties (76.5%)
Late-onset emotional and behavior challenges (10.1%)
Early challenges in both behavior and thinking skills (8.6%)
Persistent difficulties across time (4.8%)
By adolescence, kids in the late-onset and persistent groups were much more likely to struggle with mental health. In fact, even children with strong cognitive skills but early emotional struggles had more than double the risk of later mental health concerns. But here’s the encouraging part:
The link between early emotional difficulties and teen mental health weakened by age 17, suggesting that adolescence is still a key window for change. Meanwhile, early challenges with self-regulation showed stronger ties to long-term physical health issues (like weight), pointing to different timelines for different types of intervention.
Why This Matters
Early signs aren’t destiny: Many children with early symptoms normalize over time (e.g. preschool peaks that resolve); others may develop emerging difficulties later.
Symptom timing varies: Some kids show anxiety around age 5, others only during puberty. Timing—and context—plays a key role.
Risk factors inform likelihood, not certainty: Genetic vulnerability, stress exposure, or early regulation challenges increase the odds of later difficulties, but protective supports like emotion coaching, strong relationships, and tailored intervention can shift trajectories.
What to Know (and Watch For) by Age
Emotional Dysregulation in Early Childhood
Examples: Toddler outbursts, quick frustration, difficulty calming down
What to Watch For:
Many kids improve with age, co-regulation, and predictable routines.
For some, challenges may persist or shift into anxiety or conduct issues.
Support Strategies:
Use emotion coaching: label feelings, offer calming tools, stay regulated yourself.
Watch for patterns that persist beyond preschool and consider added supports.
Anxiety or Sadness in Young Children
Examples: Worrying, tearfulness, clinginess
What to Watch For:
It’s common for kids to show temporary struggles tied to transitions or stress.
Some kids follow rising or persistent anxiety trajectories and patterns into later childhood.
Support Strategies:
Validate emotions and practice small coping strategies like deep breathing or talking it out.
Keep an eye on changes in sleep, appetite, or avoidance and adjust support if needed.
Peer and Behavior Challenges in Middle Childhood
Examples: Social conflict, defiance, classroom behavior issues.
What to Watch For:
These can improve or shift into mood or behavioral issues in adolescence.
Peer struggles and academic stress can be risk points.
Support Strategies:
Scaffold social and emotional skills through guided reflection and practice.
Focus on problem-solving, not punishment, especially after the moment has passed.
Ensure kids have access to supportive adults and peers.
Long Story Short
Early mental health symptoms don’t always predict a diagnosis, and many kids’ difficulties improve over time. But others may experience emerging concerns later. It’s the patterns that matter the most, not just the symptoms.
Quick Takeaways
Mental health symptoms follow multiple paths—some resolve, some persist, some shift into new challenges.
Risk factors matter, but aren’t destiny. Supportive environments and skills make a difference.
Timing and context shape outcomes. The same symptom at age 5 may mean something different at age 15.
Developmental understanding matters more than labels. Watching for patterns over time leads to better support.
Understanding patterns, not just signs, helps us offer the right support, at the right time, with the right lens.
References
Black, M., Adjei, N. K., Strong, M., Barnes, A., Jordan, H., & Taylor-Robinson, D. (2023). Trajectories of child cognitive and socioemotional development and associations with adolescent health int he UK Millennium Cohort Study. The Journal of Pediatrics, 263(113611). doi:10.1016/j.jpeds.2023.113611
Cyr, M., Zheng, Y., & McMahon, R. J. (2022). A long-term look at “early starters”: Predicting adult psychosocial outcomes from childhood conduct problem trajectories. Development and Psychopathology, 34(1), 225–240. doi:10.1017/S0954579420000760
de Lijster, J.M., van den Dries, M.A., van der Ende, J. et al. (2019). Developmental trajectories of anxiety and depression symptoms from early to middle childhood: A population-based cohort study in the Netherlands. Journal of Abnormal Child Psychology, 47, 1785-1798. doi:10.1007/s10802-019-00550-5
Kaman, A., Devine, J., Wirtz, M. A., Erhart, M., Boecker, M., Napp, A-K., Reiss, F., Zoellner, F., & Ravens-Sieberer, U. (2024). Trajectories of mental health in children and adolescents during the COVID-19 pandemic: Findings from the longitudinal COPSY study.
Katsantonis, I. G. (2024). Development of Internalizing Mental Health Symptoms from Early Childhood to Late Adolescence. European Journal of Investigation in Health, Psychology and Education, 14(8), 2404-2416. doi:10.3390/ejihpe14080159
Oerlemans, A. M., Wardenaar, K. J., Raven, D., Hartman, C. A., & Ormel, J. (2020). The association of developmental trajectories of adolescent mental health with early-adult functioning. PLoS ONE 15(6): e0233648. doi:10.1371/journal.pone.0233648
Yes, yes, yes -- This is exactly why early conversations about mental wellness matter. Early support has the power to change life-long trajectory. Great piece.