Kevin, as I understand the current interpretation, if a child is born outside the US and the mother is a US citizen, the child is automatically a US citizen, regardless of the father's citizenship. It's automatic. The child's birth certificate with the mother's name on it is the only paperwork that's needed.

However, if the father is a US citizen but the mother is not, citizenship is not automatic. The father must file an application for US citizenship on behalf of the child prior to his sixth birthday.