Not if their father (or mother) were a foreign national at the time of their birth. They would be considered citizens, but not NBC. The child would be born with foreign citizenship (allegiance)...in the case of being born to a British Subject. We know the framers wanted to prevent such foreign influence on the position of POTUS.
What specific passage in the Constitution addresses this precise definition of Natural Born Citizen and, if you can point it out to me, why did Chief Justice John Roberts willingly disregard it when he administered the Oath of Office to Obama?