Personality resemblances in adoptive families when the children are late-adolescent or adult.

Members of 220 families who had adopted children at least 14 yrs previously completed the California Psychological Inventory and Thurstone Temperament Schedule to investigate personality resemblances among adoptees and their adoptive families. Adopted children were in late adolescence or adulthood. Results show that, consistent with other recent adoption studies, there was little resemblance between parents and adopted children or between adopted and natural siblings. The presence of a biological relationship raised correlations slightly, suggesting that much of the explanation for personality variation lies in within-family environmental variation or nonadditive genetic effects. It is noted that, in previous research, young adopted children were better adjusted on the average than biological children in the same families; however, this was no longer true for the late adolescents and young adults of the present study. (17 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)