[Calculation of the plausibility of fatherhood on the basis of blood group results in special cases using weighted Y/X values in order to respect the results from sibling of included persons. Case 2: Probability of two men, one of these is deceased, to be the father of dizygotic twins, using the blood group findings of the twins and their mother, the man alive and five legitimate children of the deceased man and their mother (author's transl)].