Child internalizing and externalizing behavioral problems are highly prevalent psychiatric symptoms worldwide, for which maternal prenatal stress is a known risk factor. However, underlying neuroendocrine mechanisms remain largely unclear. We investigated whether maternal hair cortisol (HCC) and cortisone concentration (HCNC) are associated with offspring's internalizing and externalizing behavior problems in a prospective pre-birth cohort study from Perú. N = 271 mother-child dyads were included in this analysis. Recruitment and data collection took place at the Instituto Nacional Materno Perinatal in Lima, Perú. HCC and HCHC were obtained from hair segments representing up to 3 months pre-pregnancy and first trimester, respectively, and were quantified via liquid chromatography tandem mass spectrometry. The Child Behavior Checklist was used to assess internalizing and externalizing behavioral problems of children (mean age at follow-up = 6.98 years (SD = 1.05)). Marginal structural models estimated population average associations between HCC, HCNC, and internalizing and externalizing problems, adjusting for established covariates. At pre-pregnancy, logHCNC was positively associated with offspring internalizing (β = 2.21, 95% CI: 0.46; 3.96, p = .013) and externalizing problems (β = 1.87, 95% CI: 0.34; 3.40, p = .016). At the first trimester, logHCNC was negatively associated with internalizing (β = -2.51, 95%CI: -4.37; -0.64, p = .008), and externalizing problems (β = -2.73, 95% CI: -4.18; -1.28, p < .001). Associations were stronger for females and not apparent for logHCC. We found time-dependent associations between stress-related prenatal hair glucocorticoid concentration and offspring behavioral problems. Modeling biomarker data time-dependently may prove critical to identifying the underlying mechanisms of transgenerational stress transmission.

Attachment theory, with its core concepts, perspectives, and insights developed over the past five decades, is influential for professionals working with young children. However, practitioners face challenges translating attachment theory and research into practical applications. This manifests in attachment myths, theoretical misinterpretations, and inconsistency of application. This state-of-the-art review is authored by 47 attachment researchers and practitioners and examines key insights from attachment theory to facilitate attachment-aware practice for professionals working with children and their caregivers. Following the ongoing debate on practical relevance in attachment theory, we present both 'strict' and 'expansive' translational perspectives on applications for addressing preventative or clinical attachment concerns. We first review core attachment propositions, based on replicated research of attachment and caregiving. We next address common misconceptions that hinder adequate practical applications. We present measures of attachment and sensitive parenting that might be helpful for practitioners. We also review evidence-based and promising attachment interventions, discussing core components of (preventative) support for parents or caregivers and the children in their care. We emphasize that attachment theory's clinical value lies not in assigning attachment classifications, but rather in understanding crucial insights into caregiving and early socioemotional development (e.g., secure base phenomena; the value of safe, stable, and shared good-enough care), developed in attachment research over the past 50 years, that may inform policy and clinical reasoning and areas for prevention and intervention.

In a contribution to this year's Annual Research Review, Graham Moore (Journal of Child Psychology and Psychiatry, 2026) presents a thought-provoking consideration of school climate. Highlighting the contestations in this concept, he describes how school climate might (or might not) impact child and adolescent mental health; how interventions to improve school climate might (or might not) improve child and adolescent mental health; and how school climate, and interventions to improve school climate, relate to health inequalities in young people. Moore's review generates several possibilities and opportunities, several of which are discussed below.

Providing accessible CBT for young children identified as at risk for anxiety disorders through screening in schools could reduce later problems. This study aimed to evaluate the effectiveness of parent-led CBT delivered via online and telephone call support alongside usual school provision, compared to usual school provision only for young children identified through screening as having at least one risk. We conducted a pragmatic, parallel group, superiority cluster randomised controlled trial in 95 primary/infant schools in England. Parents of children (aged 4-7) in sampled classes completed screening, and children who screened positive for one or more risks (anxiety symptoms/inhibition/parent anxiety) were eligible for the trial. Schools (clusters) were randomised (1:1) to intervention or usual school practice, stratified by school-level deprivation. Schools in both arms continued with usual provision, and parents in intervention schools were offered parent-led CBT via online and telephone support. The primary outcome was the presence of an anxiety disorder diagnosis at 12 months, assessed via the ADIS-P administered by independent assessors. Secondary clinical outcomes included parent-reported child anxiety symptoms, related interference, externalising symptoms, additional risks and intervention targets at 12 weeks and 12 months. Primary analyses were conducted on the full intention-to-treat population. The trial was prospectively registered with ISRCTN 82398107. In total, 2,328 children were screened; 1,172 were eligible; 865 enrolled. Forty-eight schools (434 children) were assigned to intervention and 47 schools (431 children) to usual school practice. At 12 months, the overall frequency of anxiety disorders was low, 6.8% (21/310) of children in the intervention arm compared to 11.5% (36/312) in the usual school practice arm; this difference was not statistically significant (adjusted odds ratio 0.67 [0.37 to 1.21], p = .19). However, the intervention was superior to usual school practice across all secondary outcomes (standardised mean difference: 0.15 to 0.47 at 12 weeks; 0.19 to 0.41 at 12 months). No serious adverse events were reported. Although the intervention did not significantly reduce anxiety disorders at 12 months, improvements across all other assessed outcomes indicate this approach brings wider immediate benefits and reduces known risks for future anxiety disorders. Future research needs to consider longer-term preventative effects.

In their review article, Developmental Language Disorders: A Hidden Condition with Lifelong Impact, Iverson and Williams (2026) cover all the ground from the importance of language and its infusion across daily tasks to the characteristics, assessment and management of a neurodevelopmental condition known as Developmental Language Disorder (DLD). The former is an important inclusion to understanding the impact of the latter, and so my commentary discusses both components. The article concludes with major challenges to investigations and support of DLD, which I add to and join in the call to raise awareness of this hidden and lifelong condition.

Eating disorders (EDs) are among the most severe psychiatric conditions emerging in adolescence, yet they remain markedly underrepresented within neuroscience and developmental psychopathology research. Building on the review by Hagan etal., this commentary proposes four key expansions to advance neurobiological research in youth with EDs: adoption of transdiagnostic approaches, inclusion of broader developmental and longitudinal time frames, implementation of more rigorous and replicable methodological frameworks, and deeper interdisciplinary integration. Together, these directions aim to more fully capture neurobiological mechanisms underlying ED onset, maintenance, and recovery across development, with the goal of anchoring this research more firmly within child and adolescent psychiatry. Taken together, the work by Hagan etal. serves as both a synthesis of the field and a call to action toward a more integrated and developmentally informed understanding of eating disorders.

Within-family designs are increasingly used to decompose genotype-trait associations into direct and indirect genetic effects. Many such designs, including trio designs or within-sibship designs, assume an absence of sibling indirect genetic effects. We expand two well-known molecular genetic within-family designs, one variance component (genome-based restricted maximum likelihood) and one trait-based (structural equation modeling with polygenic indices), to estimate sibling indirect genetic effects, along with direct genetic effects. We link the Norwegian Mother, Father, and Child Cohort Study (MoBa) to Norway's national education database to model genetic effects on national standardized testing results at ages 10, 13, and 14, and on parent-rated attention-deficit hyperactivity disorder (ADHD) symptoms at ages 3 and 8 in up to 15,971 genotyped and phenotyped siblings. Estimates of direct and indirect genetic effects from the genome-based restricted maximum likelihood and the structural equation modeling with polygenic indices approaches converge, albeit with the variance component estimates typically an order of magnitude greater than the trait-based estimates. We observe no indirect genetic effects of siblings on educational performance at any age, and only slightly negative indirect genetic effects of siblings on ADHD symptoms at age 3. We argue that the latter effect might reflect parental contrasting ratings. The results suggest that within-family models of educational performance are unlikely to be drastically biased by an assumption of absent sibling indirect genetic effects. Combining trait-based analyses with variance component analyses can benefit understanding of indirect genetic effects, especially when the effects are not specific to a particular mechanism.

Violence exposure is a well-established risk factor for adolescent conduct problems, yet longitudinal research in high-adversity, low- and middle-income countries (LMICs) remains limited. This study investigated whether early adolescent violence exposure predicts concurrent and longer-term conduct problems, and explored potential bidirectional associations and sex differences in a peri-urban South African community with high rates of poverty and violence. Data were drawn from the Thula Sana birth cohort (n = 357; 51.5% female), a longitudinal intervention study in Khayelitsha, South Africa. Adolescents were assessed at early (ages 12-14) and late adolescence (ages 16-19). Violence exposure was measured using adolescent self-report. Conduct problems were measured using adolescent and caregiver report in early adolescence and adolescent self-report in late adolescence. Multiple linear regressions tested cross-sectional associations, and cross-lagged panel models examined longitudinal and bidirectional associations, adjusting for contextual adversity and intervention status. Missing data were addressed using multiple imputation, and findings were confirmed through sensitivity analyses. Violence exposure was associated with higher concurrent conduct problems in early adolescence (β = .15-.19, p < .01) and predicted higher conduct problems in late adolescence (β = .12-.14, p < .05). The reverse pathway, from conduct problems to subsequent violence exposure, was not significant (β = .08-.11, p > .05). Interaction analyses did not provide evidence that associations differed by sex. Violence exposure in early adolescence represents a prospective risk factor for conduct problems in a high-adversity South African setting. Findings highlight the importance of early, contextually grounded violence prevention and the need for further research to test sex-specific pathways and inform the development of gender-responsive intervention strategies.

Domestic violence mechanisms are frequently transmitted across generations, representing a global issue demanding particular attention. This study investigates the intergenerational transmission of intimate partner violence (IPV) and parent-to-child violence (PCV) and whether participating in a multilevel preventive intervention (Fast Track) breaks this transmission. In high-risk elementary schools located in the United States, children considered at high risk for aggressive behavior based on teachers' and parents' screen scores were assigned to either a 10-year intervention or a control group based on their school. The Fast Track trial was registered at clinicaltrials.gov (NCT01653535) and was focused on parenting practices and children's intrapersonal, interpersonal, and academic skills. From the original 891 children, 374 participants with children aged less than 18 years (n = 191 intervention group, n = 183 control group) reported at age 34 their experience with domestic violence and their children's psychological adjustment. The intergenerational mediating pathway from high IPV in the first generation to high PCV in the second generation to greater total mental health difficulties in the third generation was statistically significant in the control group but not in the intervention group. IPV was intergenerationally transmitted by influencing PCV, with a negative effect on the third generation's mental health. Nevertheless, participation in the Fast Track intervention disrupted this cycle. These findings suggest the importance of policies to support preventive childhood interventions.

Parent-child interaction therapy (PCIT) improves parenting and child behavior, yet little is known about how dosage of its two phases, warm relationship building focused child-directed interaction (CDI) sessions and safe, effective discipline skills-focused parent-directed interaction (PDI) sessions, contributes to outcomes, particularly in child welfare-involved families. Understanding these dose-response patterns can clarify the pathways through which PCIT produces change. In a sample of 204 child welfare families with young children, we examined the dose-response relationship between each PCIT phase and key intervention outcomes of positive and negative parenting skills and disruptive child behavior problems. We also used sequential mediation models to test time-ordered intervention dosage effects (i.e., number of CDI sessions completed and subsequent number of PDI sessions completed) on the parent and child outcomes. Sequential mediation models showed that the PCIT intervention exerted significant indirect effects on increased positive parenting skills and decreased negative parenting behaviors and child behavior problems through higher dosage of relationship-enhancing CDI sessions followed by higher dosage of safe discipline-focused PDI sessions. Further, CDI dosage interacted with PDI dosage to predict greater gains in positive parenting skills outcomes. These results contribute new insights into the pathways through which PCIT shapes outcomes in a sample of child welfare-involved families. Findings also highlight the significant unique contribution that limit-setting-oriented PDI, a relatively understudied phase of PCIT, plays in enhancing positive parenting skills and mitigating child behavior problems.