ИСТИНА

We studied self-evaluations of the Dark Triad and some other personal characteristics of siblings (28 indicators). The hypothesis of bigger similarity of self-evaluations of personal characteristics in case of same-sex sibling pairs compared with opposite-sex sibling pairs was examined. Participants. One hundred ninety-eight people participated in the experiment (99 sibling pairs: 55 same-sex and 44 opposite-sex pairs). The eldest sibling’s mean age was 23.3, SD = 3.47, the youngest's was 20.5, SD = 2.76 years. Procedure. Participants were offered to fill in seven questionnaires according to two instructions. At first they defined one’s agreement with questions or statements. Then the respondents filled in the same questionnaire for his/her sibling: How in your opinion would your sibling answer? Measures. We used Eysenck's Personality Inventory, Locus of Control Questionnaire, the Dirty Dozen Questionnaire, the Dark Triad Questionnaire, the Short Big 5, the Tolerance Scale, and Zuckerman's Sensation Seeking Scale for self-evaluations. Conclusions. The results obtained confirm that the same-sex or opposite sex (in the case of siblings) significantly influence the number and structure of relationships of self-evaluations of the Dark Triad features inside the pair-between each other and with other personal characteristics. Same-sex siblings have nearly twice as many significant relationships of self-evaluations of personal characteristics inside pairs than opposite-sex siblings. It is possible to suppose that the same sex of siblings does not only objectively help formation of similarity inside the pair but also generates convergent trend for bigger identification of oneself with one’s sibling.