Differential parenting as a within-family variable

Nonshared environmental influences have been found to be important for adol escent development. This study of 516 families investigated whether differe ntial parental negativity or warmth is linked to adolescent adjustment apar t from the effect of the level of parenting toward each child separately. A fter accounting for level of parental treatment to the adolescent, the auth ors found that differential parenting to the siblings contributed unique va riance in adjustment. Significant interactions were found between level of parenting and differential parenting. In each case, differential parenting was more strongly linked to adjustment when the level of parenting was low in warmth or high in negativity. These results are indirect evidence that d ifferential parenting can be considered a within-family influence on siblin g adjustment and as direct evidence that nonshared environmental factors ma y systematically vary in strength between families.