From this study it appears that sibling position plays no important part in the development of schizophrenia. There is some evidence to show that the stress to which the middle child is subjected may increase the incidence of the disorder in children occupying this ordinal position. The only child is not subjected to sibling stress and is accordingly slightly less likely to develop schizophrenia. The study as a whole indicates that this disorder is prone to occur in a certain characteristic personality pattern, the incidence of which is approximately the same in all siblings regardless of their position in the family.Abstract Teaser