Unless Obama’s father is somebody other than Barack Hussein Obama Sr. of Kenya, he is not a natural born citizen at all. BHO, Sr. was never any kind of citizen of the US and his mother was too young to confer her citizenship on him, according to hawaiian law at the time. At best, he is a dual citizen of Britain and the US — a fact he stated in his Bio.
Now, if his real father is somebody else, then he is (perhaps) a natural born citizen. But, where does that leave his adoption by Lolo Soetero and little Barry Soetero’s declaration of Indonesian citizenship? Did he ever reinstate his US citizenship after Ann Dunham divorced his adoptive father? Since all of the records are deliberately sealed, we’ll never know.
The questions linger.
The father's citizenship requirement is debatable and the mother's age is applicable only if he was born overseas.