DNA methylation (DNAm) is known to play a pivotal role in childhood health and development, but a comprehensive characterization of genome-wide DNAm trajectories across this age period is currently lacking. We have therefore performed a series of epigenome-wide association studies in 5019 blood samples collected at multiple time-points from birth to late adolescence from 2348 participants of two large independent cohorts. DNAm profiles of autosomal CpG sites (CpGs) were generated using the Illumina Infinium HumanMethylation450 BeadChip. Change over time was widespread, observed at over one-half (53%) of CpGs. In most cases, DNAm was decreasing (36% of CpGs). Inter-individual variation in linear trajectories was similarly widespread (27% of CpGs). Evidence for non-linear change and inter-individual variation in non-linear trajectories was somewhat less common (11 and 8% of CpGs, respectively). Very little inter-individual variation in change was explained by sex differences (0.4% of CpGs) even though sex-specific DNAm was observed at 5% of CpGs. DNAm trajectories were distributed non-randomly across the genome. For example, CpGs with decreasing DNAm were enriched in gene bodies and enhancers and were annotated to genes enriched in immune-developmental functions. In contrast, CpGs with increasing DNAm were enriched in promoter regions and annotated to genes enriched in neurodevelopmental functions. These findings depict a methylome undergoing widespread and often non-linear change throughout childhood. They support a developmental role for DNA methylation that extends beyond birth into late adolescence and has implications for understanding life-long health and disease. DNAm trajectories can be visualized at http://epidelta.mrcieu.ac.uk.

As a result of societal changes, fathers participate more actively in child care than they used to. In this article, we propose a context-dependent biobehavioral model of emergent fatherhood in which sociocultural, behavioral, hormonal, and neural factors develop and interact during the first 1,000 days of fatherhood. Sociocultural factors, including different expectations of fathers and varying opportunities for paternal caregiving through paid paternal leave, influence paternal involvement. Levels of hormones (e.g., testosterone, vasopressin, oxytocin, cortisol) predict fathers’ parenting behaviors, and involvement in caregiving in turn affects their hormones and brain responses to infant stimuli. The birth of the first child marks the transition to fatherhood and may be a critical period in men’s lives, with a smoother transition to fatherhood predicting more optimal involvement by fathers in subsequent years. A focus on prenatal and early postnatal fathering may pave the way for developing interventions that effectively support fathering during pregnancy and in the first years of their children’s lives.

Attachment theory and research are drawn upon in many applied settings, including family courts, but misunderstandings are widespread and sometimes result in misapplications. The aim of this consensus statement is, therefore, to enhance understanding, counter misinformation, and steer family-court utilisation of attachment theory in a supportive, evidence-based direction, especially with regard to child protection and child custody decision-making. The article is divided into two parts. In the first, we address problems related to the use of attachment theory and research in family courts, and discuss reasons for these problems. To this end, we examine family court applications of attachment theory in the current context of the best-interest-of-the-child standard, discuss misunderstandings regarding attachment theory, and identify factors that have hindered accurate implementation. In the second part, we provide recommendations for the application of attachment theory and research. To this end, we set out three attachment principles: the child’s need for familiar, non-abusive caregivers; the value of continuity of good-enough care; and the benefits of networks of attachment relationships. We also discuss the suitability of assessments of attachment quality and caregiving behaviour to inform family court decision-making. We conclude that assessments of caregiver behaviour should take center stage. Although there is dissensus among us regarding the use of assessments of attachment quality to inform child custody and child-protection decisions, such assessments are currently most suitable for targeting and directing supportive interventions. Finally, we provide directions to guide future interdisciplinary research collaboration.

In a longitudinal study with 125 early adopted adolescents, we examined continuity of attachment from infancy to adolescence and the role of parental sensitive support in explaining continuity or discontinuity of attachment. Assessments of maternal sensitive support and infant attachment (Strange Situation Procedure) were completed when infants were 12 months old. When the children were 14 years old, we observed mothers' sensitive support during a conflict discussion. The adolescents' attachment representations were assessed with the Adult Attachment Interview. Mothers of secure adolescents showed significantly more sensitive support during conflicts than did mothers of insecure adolescents. Overall, no continuity of attachment from infancy to adolescence was found. However, maternal sensitive support in early childhood and adolescence predicted continuity of secure attachment from 1 to 14 years, whereas less maternal sensitive support in early childhood but more maternal sensitive support in adolescence predicted children's change from insecurity in infancy to security in adolescence. We conclude that both early and later parental sensitive support are important for continuity of attachment across the first 14 years of life.

Improving parenting, child attachment, and externalizing behaviors: Meta-analysis of the first 25 randomized controlled trials on the effects of Video-feedback Intervention to promote Positive Parenting and Sensitive Discipline (VIPP-SD). VIPP-SD combines support of parental sensitive responsiveness with coaching parents in sensitive limit setting. Here, we present meta-analyses of 25 RCTs conducted with more than 2,000 parents and caregivers. Parents or children had various risks. We examined its effectiveness in promoting parental cognitions and behavior regarding sensitive parenting and limit setting, in promoting secure child–parent attachment, and reducing externalizing child behavior. Web of Science, MEDLINE, PubMed, and recent reviews were searched for relevant trials (until May 10, 2021). Multilevel meta-analysis with META, METAFOR, and DMETAR in R took account of the 3-level structure of the datasets (studies, participants, measures). The meta-analyses showed substantial combined effect sizes for parenting behavior (r = .18) and attitudes (r = .16), and for child attachment security (r = .23), but not for child externalizing behavior (r = .07). In the subset of studies examining effects on both parenting and attachment, the association between effect sizes for parenting and for attachment amounted to r = .48. We consider the way in which VIPP-SD uses video-feedback an active intervention component. Whether VIPP-SD indeed stimulates secure attachment through enhanced positive parenting remains an outstanding question for further experimental study and individual participant data meta-analysis.