I have never thought so. It’s what Orly Taitz is claiming. In fact, she claims one must have TWO citizen parents, AND be born on U.S. soil, to be “natural-born.”
I have always thought that even “anchor babies” are “natural-born” citizens, for the simple reason that they are citizens at the moment they are born.
After Soetoro, I’d like to see the Constitution amended to say that one must have four grandparents and both parents citizens.
Anchor babies born in the US are “Native Born”. They do have U.S. Citizenship but are not eligible for POTUS since they are not “Natural Born U.S. Citizens”.