There is available an extensive literature relating to birth order and its possible effect on the incidence of psychiatric disorder, on character, or on patterns of personality development. Little attention has been given to the distribution of sex within sibships. A study is reported on the sibships of 400 consecutive psychiatric admissions. The preceding sibships show an increase in same sexed members. This effect is most obvious in larger sibships and for the penultimate member. This may be due to a series of children of the same sex born into a family. Finally a child of the desired opposite sex is born and the family completed.
References
1.
AbrahamsM. J.WhitlockF. A. (1969). Childhood experience and depression. Brit. J. Psychiat., 115: 883.
2.
AlanenY. O. (1958). Mothers of schizophrenics. Acta psychiat. neurol. scand. Supplement124.
3.
BirtchnellJ. (1970a). Early parent death and mental illness. Brit. J. Psychiat. 116: 281.
4.
BirtchnellJ. (1970b). Recent parent death and mental illness. Brit. J. Psychiat. 116: 289.
5.
BirtchnellJ. (1970c). Depression in relation to early and recent parent death. Brit. J. Psychiat. 116: 299.
6.
BirtchnellJ. (1970d). The relationship between attempted suicide, depression and parent death. Brit. J. Psychiat. 116: 307.
7.
Erlenmeyer-KimlingL. (1969). The problem of birth order and schizophrenia: A negative conclusion. Brit. J. Psychiat., 115: 659.
8.
Granville-GrossmanK. L. (1968). The early environment in affective disorder. In: CoppenA.WalkA. (Eds.). Recent Developments in Affective Disorders. Brit. J. Psychiat. Special Publication No. 2. Headley Bros., Ashford.
9.
GregoryI. (1960). Genetic factors in schizophrenia. Amer. J. Psychiat., 116: 961.
10.
GregoryI. (1962). Selected personal and family data on 400 psychiatric patients. Amer. J. Psychiat., 119: 397.
11.
GregoryI. (1966). Retrospective data concerning childhood loss of a parent. Arch. gen. Psychiat., 15: 362.
12.
HareE. H.PriceJ. S. (1969). Birth order and family size: bias caused by changes in birth rate. Brit. J. Psychiat., 115: 647.
13.
HinshelwoodR. D. (1970). The evidence for a birth order factor in schizophrenia. Brit. J. Psychiat., 117: 293.
14.
LindsayJ. S. B. (1965). The length of treatment. Brit. J. soc. clin. Psychol., 4: 117.
15.
PriceJ. S.HareE. H. (1969). Birth order studies: Some sources of bias. Brit. J. Psychiat., 115: 633.
16.
SchmuckR. (1963). Sex of sibling, birth order position and female disposition to conform in two-child families. Child Development, 34: 913.
17.
SchoolerC. (1961). Birth order and schizophrenia. Arch. gen. Psychiat., 4: 91.
