http://federalistblog.us/2008/11/natural-born_citizen_defined.html
The Fourteenth Amendment framer, Rep. John A. Bingham, in 1871, gave a definition of Natural Born Citizen, which stated in part:
every human being born within the jurisdiction of the United States of parents not owing allegiance to any foreign sovereignty is, in the language of your Constitution itself, a natural born citizen.
So, to restate Rep. Bingham’s definition of “natural born” in 21st century terms:
1. Born on U.S. soil;
2. Parents are citizens at the time of birth.
I’m not making this stuff up, you know!
Too bad we don't have any commentary from any of the attendees at the constitutional convention on this subject, at least none that I'm aware of.