> Another question: Which year was the first Robert that came to America born?
Bluntly, we do not know.
Despite all the claims that you may find online (and some lovely myths!), any date of birth for the first Robert that you can find is mere guesswork and no better.
Many have claimed to have concrete evidence and proof of parentage, but pressure them and they quickly and silently disappear into the woodwork, never to be encountered again. No one has yet been willing (or able) to give enough specifics that would allow any present day researcher (even the very highly paid and duly certified professionals who routinely do research at the PRO and are well acquainted with that facility and unique catalogue) to find what many of us dream of finding!