II. Natural, Common, and Civil Law.Natural law belongs to all animals. Yet there is no such thing as natural born citizenship for animals, only men. So natural born citizen cannot be a natural law. Therefore it has to be common or civil law according to the source you cited.The law of nature is that law which nature teaches to all animals. For this law does not belong exclusively to the human race, but belongs to all animals, whether of the earth, the air, or the water. Hence comes the union of the male and female, which we term matrimony; hence the procreation and bringing up of children. We see, indeed, that all the other animals besides men are considered as having knowledge of this law.
It could be an unwritten law.
9. The unwritten law is that which usage has established; for ancient customs, being sanctioned by the consent of those who adopt them, are like laws.You left out the important part of the following quote.
11. The laws of nature, which all nations observe alike, being established by a divine providence, remain ever fixed and immutable. But the laws which every state has enacted, undergo frequent changes, either by the tacit consent of the people, or by a new law being subsequently passed.God says who is a natural man. Man says who is a natural born citizen.
“God says who is a natural man. Man says who is a natural born citizen.”
Please show me where the Founders said who is a natural born citizen.