Apparently Hillel was a grandson of King David according to tradition

Regarding Yael Ziskin's account, etc., all the Ashkenazim are grandchildren of Rashi and this is known and clarified {but not son after son because Rashi had no sons, only daughters} but mixed

But according to Yael Ziskin's account, if you go from above to us, you can also go the other way around. I have one father, he was his father's son, his father's son

And the father of my father's father in the generation of King David was only A and that is already less than a little percent that you and I are son after son of King David and what according to the calculation he had two sons and if he also had two sons then this is no longer accurate as we know that in past years there were many Children and people who have passed away, so son after son is not possible, but a grandson is sure to be sure that we are all his grandchildren

Moshe Gizbar

Grandson of the first Adam