I know it, you know it, SCOTUS has ruled on it, and every constitutional scholar on Earth knows it, but the birthers will refuse to believe you no matter what evidence you present to them. Jesus Christ himself could descend from the clouds and personally reveal it to them, and yet they still wouldn't believe it.
Unless you enjoy banging your head against the wall, I wouldn't recommend getting into any extensive discussions on this matter.
The SCOTUS ruled on two occasions that you must be born in the country to citizen parents in order to be a natural born citizen. Helps to read the actual decisions instead of faither talking points.