Claims little factual evidence exists for proposition that child rearing styles and family environments are formative of personality traits. Contends nonintellectual traits seem to be determined instead by genetic influences and relatively specific environmental influences, most of which are particularly tied to the family or parental treatments.…

The research described in this article addressed the question of why siblings commonly have different developmental outcomes despite their common beginnings. The studies analyzed behavioral development, especially through examination of deviant behaviors and intellectual development, by tracing siblings' different life histories. The work is based…