Studies of adolescent or parent-based twins suggest that gene-environment correlation (rGE) is an important mechanism underlying parent-adolescent relationships. However, information on how parents' and children's genes and environments influence correlated parent "and" child behaviors is needed to distinguish types of rGE. The present…

Research suggests that sibling--peer connections are important for understanding adolescent problem behaviors. Using a novel behavioral genetic design, the current study investigated peer network overlap in 300 child--child pairs (aged 7-13 years) in 5 dyad types: monozygotic (MZ), dizygotic twins, full siblings (FSs), friend pairs, and virtual…

A critique of research examining whether early experiences with primary caregivers are reflected in adaptation is that relevant longitudinal studies have generally not employed genetically informed research designs capable of unconfounding shared genes and environments. Using the twin subsample (N = 485 pairs) of the Early Childhood Longitudinal…

Although a negative association between hyperactivity and academic achievement is well documented, little is known about the genetic and/or environmental mechanisms responsible for the association. The present study explored links between parent and teacher ratings of hyperactive behavior problems and teacher-assessed achievement in a sample of…

Parents of Swedish twin pairs ages 7 to 9 years and of British twin pairs ages 8 to 16 years completed the Child Behavior Checklist. Found that genetic factors influenced aggressive antisocial behavior to a greater extent than nonaggressive antisocial behavior, which was also significantly influenced by the shared environment. There was a…

Data were analyzed from an epidemiological sample of 5-year- old twins and their parents. Findings indicated that the less time fathers lived with their children, the more conduct problems their children had, but only if the fathers engaged in low levels of antisocial behavior. When fathers engaged in high levels of antisocial behavior, the more…

Examined environmental and gene-environment processes linking parenting (affect, control, responsiveness) and preschoolers' behavioral adjustment difficulties (noncompliance, conduct problems). Found that estimates of shared environmental variance and mediation were greatest for observational data, and estimates of child genetic variance and…

Examined nonshared environmental (NSE) influences on twin preschoolers' behavior independent of genetics. Found that within-pair parenting differences correlated with monozygotic differences in behavior. For the extreme 10 percent of the parenting-discordant and behavior-discordant distributions, average NSE effect size was 11 percent, suggesting…