If you’re having to refer to statute, then that’s not natural born citizenship.
Congress was enumerated power over immigration and naturalization, only. Laws on the books must be construed to deal with immigration and naturalization only, as a result. Otherwise, such statute would be unconstitutional.
All citizens have the same rights and duties, excepting as the Constitution makes a distinction, and only the Constitution makes any distinction.
That distinction being eligibility to various national offices, by age, plus length of residency or birth status, increasingly narrow as the level of official capacity increases.
Natural born citizenship only pertains, legally under the Constitution, to the Executive branch, regarding eligibility to the Office of President. Eligibility to succeed the President in turn implies the requirement upon the line of succession.
I have a French birth certificate with a US state department certificate of being born abroad.
For the purpose of my part of the discussion, I really don't care whether Ruth Buzzy's grandson is a NBC, but from RC's discussion, it seems highly likely that dependence upon US law for citizenship is ipso facto not naturally born citizenship, nor would it be Congress' jurisdiction, as such is not enumerated to them.
Contrary to what you said, Barry Soetero's citizenship and potential NBC status would be judged entirely without regard to Buzzy's progeny being any kind of citizen, except perhaps in Buzzy's mind.
Condor51 is saying BHO qualifies as a citizen at birth under US Code, Title 8, Chapter 12, Subchapter III, Part I, paragraph g, but that would inherently mean not a NBC, as it is dependent on statute, not NBC defintion.
From all the publicly known information in combination with the above citation, BHO seems to have been born a US citizen, even if he was born in Kenya, and so long as Indonesia's adoption procedures can't nullify Zero's access to prior US citizenship, which I'm reasonably confident must be the case, but perhaps only if he availed himself of the proper US paperwork once he became of age.
Though I'd read of the five-year requirement on Stanley Ann, I hadn't seen before that only two years of those needed to be as of the age of fourteen, which she seems to have met.
With this distraction in his hip pocket, I believe the info on his Hawaiian COLB will show Barry to have been lying fraud for many years prior to his presidency, most likely as to his having been born in Kenya, but certainly not to a degree that will get him impeached in this session of Congress. That said, it would be important to note that his having been truthful on that point would certainly have kept him from getting elected president.
HF