This study examined cumulative risk, temperament traits, and their interplay as predictors of internalizing, externalizing, and sleep problems in at-risk toddlers. Participants were 104 low-income mother-toddler dyads recruited from Women, Infants, and Children (WIC) sites in a large city. The sample was primarily African American, and mothers were 21 years of age or younger at the child's birth. The dyads were assessed when the toddlers were approximately 18 months old and again at 24 months of age. Though all toddlers were from low-income families with young mothers, the families varied in the degree to which other contextual risk factors were present. A cumulative risk index was calculated based on five contextual factors: maternal education, neighborhood dangerousness, social support, household overcrowding and single parenting. In multiple regressions, cumulative risk predicted sleep and externalizing problems. In addition, negative affectivity predicted all three domains of problem behaviors, effortful control predicted fewer externalizing problems, and surgency predicted fewer internalizing problems. Moreover, low negative affectivity buffered the association between cumulative risk and both internalizing and sleep problems. These findings suggest that it is important to consider children's temperament traits in conjunction with the constellation of family risks when designing prevention programs to reduce the prevalence of behavior problems early in life.
Keywords: at-risk families; behavior problems; cumulative risk; temperament; toddlers.