This preregistered, longitudinal study examined how much adolescents value and integrate their parents' and peers' attitudes into their own attitudes from early to middle adolescence. Across three waves, participants (N = 172, 91 female, 11-16 years across three waves; 439 data points) decided whether to pay money to learn their parents' or peers'…

Prior research suggests that human children lack an aptitude for tool innovation. However, children's tool making must be explored across a broader range of tasks and across diverse cultural contexts before we can conclude that they are genuinely poor tool innovators. To this end, we investigated children's ability to independently construct 3 new…

Children hold strong ingroup biases from a young age, liking ingroup over outgroup members and preferring them as social learning models. Simultaneously, children are also highly prosocial--both in their own helping behaviors and their avoidance of those who behave antisocially. This study explores how children of 2 age groups (4-5 and 7-8 years)…

When threatened with ostracism, children attempt to strengthen social relationships by engaging in affiliative behaviors such as imitation. We investigated whether an experience of ostracism influenced the extent to which children imitated a partner's language use. In two experiments, 7- to 12-year-old children either experienced ostracism or did…

This study examines developmental change across adolescence in the similarity of friends versus nonfriends. This differential in similarity is a key aspect of the organization of the peer context of development: The stronger the correlation between friends for an attribute, the more the attribute delineates clustering and divisions of friendships.…

Adolescence and young adulthood are characterized by substantial sociodemographic, family, social, and personality changes that may influence loneliness. Although loneliness is a public health challenge, we know little about how loneliness develops during these periods. Our study addresses this lacuna by using 4-wave longitudinal data from 3,116…

General well-being is known to deteriorate sharply at the end of life. However, it is an open question how rates of terminal change differ across affective and evaluative facets of well-being and if individual difference correlates operate in facet-specific ways. We examined how discrete affective states (happy, angry, fearful, sad) and…

Recent research questions whether children conceptualize race as stable. We examined participants' beliefs about the relative stability of race and emotion, a temporary feature. Participants were White adults and children ages 5-6 and 9-10 (Study 1) and racial minority children ages 5-6 (Study 2). Participants were presented with target children…

This study examines historical variation in age 18 to 26 binge drinking trajectories, focusing on differences in both levels of use and rates of change (growth) across cohorts of young adults over 3 decades. As part of the national Monitoring the Future Study, over 64,000 youths from the high school classes of 1976 to 2004 were surveyed at…

Adolescence is a vulnerable period for the initiation and peak of many harmful risk-taking behaviors such as smoking, which is among the most addictive and deadliest behaviors. Generic metatheories like the theory of triadic influence (TTI) suggest that interrelated risk factors across multiple domains (i.e., intrapersonal and…

The purpose of this study was to examine the associations between maternal reports of social fear at 24 months and social behaviors with an unfamiliar peer during play at 36 months, using the Actor-Partner Interdependence Model (APIM; Kashy & Kenny, 1999). The APIM model was used to not only replicate previous findings of direct effects of…

American and Japanese children's evaluations of the reporting of peers' transgressions to authority figures were investigated. Seven-, 9-, and 11-year-old children (N = 160) and adults (N = 62) were presented with vignettes and were asked to evaluate the decisions of child observers who reported their friend's either major or relatively minor…

This study examined whether the degree to which bullying is normative in the classroom would moderate associations between "intra"- (cognitive and affective empathy, self-efficacy beliefs) and "inter"personal (popularity) factors and defending behavior. Participants were 6,708 third- to fifth-grade children (49% boys;…

Children's decisions regarding the allocation of societal resources in the context of preexisting inequalities were investigated. African American and European American children ages 5 to 6 years (n = 91) and 10 to 11 years (n = 94) judged the acceptability of a medical resource inequality on the basis of race, allocated medical supplies,…

Co-rumination is a dyadic process between relationship partners that refers to excessively discussing problems, rehashing problems, speculating about problems, mutual encouragement of problem talk, and dwelling on negative affect. Although studies have addressed youths' "tendency" to co-ruminate, little is known about the nature of…