Well, I suppose in the past they could have got round this by having Princess Aiko marry a descendent of a junior branch of the imperial family so that her sons (assuming she has any, considering the recent history of the family) have imperial descent on both sides of the family. But these days it's not really realistic to expect that sort of arranged marriage, especially since none of the present emperor's children had to go through such a thing.
Seems a bit strange that nowadays, when we know how genetics work and we know that children get genes from their mother as well as their father, this would still be an issue.
Seems a bit strange that nowadays, when we know how genetics work and we know that children get genes from their mother as well as their father, this would still be an issue.
