I am an only child also, and I read a book a few years ago about only children that said a bunch of things I didn't want to hear - things like the list you posted.
Now it turns out most of the research on only children is flawed. In fact, the Wikipedia entry on only children says this:
"A 1987 quantitative review of 141 studies on 16 different personality traits contradicted Adler's theory by finding no evidence of any maladjustment in only children. The primary finding was that only children are not very different from children with siblings. The main exception to this was the finding that only children are higher in achievement motivation. A second analysis revealed that only children, first-borns, and children with only one sibling score higher on tests of verbal ability than later-borns and children with multiple siblings."
|