You might be unaware of this, but US Citizens were created by the Declaration of Independence, not the US Constitution. The US Constitution is the THIRD governing document. (It was preceded by the Articles of Confederation.)
I don't believe William Blackstone was much help in writing the Declaration of Independence. That document pretty much turns English common law on it's ear, and it is *THAT* document which created US Citizenship. If you look at the early court decisions, they regard the dividing point between citizen/subject as July 4, 1776.
Again, it was the Declaration of Independence that created the condition we call "US Citizen."
OK.
I don't believe William Blackstone was much help in writing the Declaration of Independence.
I don't see Emmerich de Vattel mentioned either.
Again, it was the Declaration of Independence that created the condition we call "US Citizen."
So where does it define natural-born citizen?