What does age have to do with being a "natural born citizen"?
I was a natural born citizen the moment of my birth, and it didn't matter how old I was, I was still a natural born citizen at any age.
What is this strange sort of citizenship of which you speak that you must qualify for by reaching a certain age?
It sounds rather unnatural.
The original question let the title was "is he eligible to be US President? Unlike the term "natural born citizen", which is specified but never successfully defined in the Constitution (much to the chagrin of internet posters everywhere), a minimum age to become President is defined as 35 and there is no legal disagreement over what "age 35" means.