“…However, overall impression from the relevant research is that birth-order has minimal effect on individual differences in personality traits or intelligence (Ernst & Angst, 1983;Schooler, 1972). A similar conclusion was derived from the early literature about the personality of only children: whatever role the mere presence or absence of siblings may play in development of personality, its importance is certainly not crucial (Campbell, 1934;Falbo ONLY CHILDREN STEREOTYPE 4 & Polit, 1986). Thus, possible differential parental treatment of children with different birth orders or only children, or competition among siblings does not seem to have a straightforward impact on people's personality traits.…”