Bingowings said:
Leia doesn't though does she?
The assumption is made by both Ben and Vader that any offspring of Anakin's would be a threat to the Emperor (who knows this) because of their mutual Force strength.
For the last time now... Anakin's offspring were a threat to the Emperor BUT in sense of triggering Anakin's return. The fact is that this is what actually killed Emperor.
On the other hand, possible inheritance of force powers (which you aim at) was never explicitly mentioned in the films NOR does it play any role in Emperor's eventual demise.
End of discussion.