Many cases of familial occurrence of congenital malformations have been reported in previous literatures. However, the etiology of congenital malformations has been controversial and unknown. The relationship between occurrences of different congenital malformations in siblings and heredity have not been clarified, too. Two cases with different congenital malformation in siblings, ruptured omphalocele in an elder sister and anal atresia in a younger brother, were presented in this paper. Four such cases of different congenital malformations in siblings have been reported previously in Japan.
