From: keith_nuttle@sbcglobal.net   
      
   On 1/22/2020 5:34 AM, Evertjan. wrote:   
   > I have a family tree whereby a group of siblings have four lines of   
   > descent from the same couple.  For three of these there are 7   
   > generations and for the other there are 6 generations.  The 7 generation   
   > descent would give 128 distinct genealogical roles at this level and the   
   > 6 generation descent would give 64.  In fact I find 10 individuals   
   > filling 24 of these roles so there are 14 "missing" ancestors due to   
   > pedigree collapse.   
   You do not mention the sex of the member of each generation. If you mean   
   by missing that you can find no one of the family name to fill the   
   missing position, then it can easily be explained by the ratio of males   
   to females.   If there are several generations where mostly females are   
   born in our society the family surname is likely to disappear for that   
   generation.   
      
   My grand father had two boys,  the boys had five boys.  Only two had one   
   boy each, and the third generation of two boys had no boys.  So for that   
   line the family surname disappears.   
      
   --- SoupGate-Win32 v1.05   
    * Origin: you cannot sedate... all the things you hate (1:229/2)