Children born in the US are considered natural born regardless of the parents' status.
From the Congregational Research Service:
"The term 'natural born' citizen is not defined in the constitution...the term 'natural born' citizen would mean a person who is entitled to U.S. citizenship 'by birth' or 'at birth, either by being born 'in' the United States and under its jurisdiction, even those born to alien parents"
On a side note, as a people trying to persuade the nation on all kinds of things, we all at DP really need to get into the habit of citing our sources. Even if we're wrong, it at least gives us some kind of starting point to engage in meaningful discussion. Sources help us go beyond the realm of opinion and at least approach the world of facts.