9. Plomin, R., & Daniels, D. (1987b). Children in the same family are very different, but why? Behavioral and Brain Sciences, 10, 44-54.

The above BBS target article elicited a record response; the purpose of the present article is to respond to 32 published commentaries. There is a consensus that children in the same family are very different from one another. There is also general agreement that most of the environmental variance is of the nonshared variety. So, the question now is, "Why?"