You’re making up the last part about parents in amity.
"Such allegiance and protection were mutual -- as expressed in the maxim protectio trahit subjectionem, et subjectio protectionem -- and were not restricted to natural-born subjects and naturalized subjects, or to those who had taken an oath of allegiance, but were predicable of aliens in amity so long as they were within the kingdom. Children, born in England, of such aliens were therefore natural-born subjects. But the children, born within the realm, of foreign ambassadors, or the children of alien enemies, born during and within their hostile occupation of part of the King's dominions, were not natural-born subjects because not born within the allegiance, the obedience, or the power, or, as would be said at this day, within the jurisdiction, of the King."
That wasn't written as a historical review, but to demonstrate the meaning of natural born citizen by examining the "precisely analogous", well established and known term (in the 1780s) 'natural born subject'.