The work aimed at grasping eventual relations between the grandparents' life length and the number of their siblings and children. A poll of 2800 students of Wroclaw higher education institutions (1023 men and 1777 women) from 18 to 26 years of age was conducted. Information concerning the number of siblings and children of the examined students' grandparents, and in case of the dead—their age at the moment of death, were used. The material was divided into two categories (using death—rate tables and death age median: short living (SL) and long living (LL). The examined relations were analyzed separately for mothers' mothers (MM), fathers' mothers (FM), mothers' fathers (MF) and fathers' fathers (FF) of the students combined these groups were also analysed. Number of siblings in the families of grandparents of the same categories of longevity generally doesn't differ significantly for each group of grandparents. Short living grandparents have significantly fewer siblings than the long living ones. Number of children, similarly as the number of siblings, is also higher in case of long living individuals. The described relation shall probably be sought in the so—called protective role of the family.

K. Boryslawki

Papers

Number of siblings and children of short and long living individuals