I don't understand what this means?
Biologically and historically, we have two parents, four grandparents, eight great grandparents etc etc.
Our foremothers can all be traced back to pre-neolithic eras. This is the case for everyone, not an elite few. And people tend to use their family name rather than creating a new one (yes, yes, there are exceptions)
So what does "an old family" actually mean?
YANBU - I haven't got a clue
YABU - Ah ha, it means this......