The democrats who certified his eligibility to be a US President either lied or know that his true father is an American citizen, but choose not to reveal who that is. Whether a lie or a lack of candor, it's made viable by the tactics of the deep state: heaping scorn and derision on anyone who doubts 0's eligibility, and spewing obfuscation of the law and facts.
It's been a long time since I've opined on this subject ... take my opinion for what it's worth ... about 2 cents.
I really don’t want to fall off into this rabbit hole ... but none of the original citizens of the U.S. had parents who were citizens, because the country did not exist when they were born.
Thus it seems to me the requirement to be a natural born citizen was to be born on the soil of the nation.