The listing of children in "The Beckwith" is apparently incomplete. And of little help is that Jennings does not show up in Beckwith listings in censuses until 1830. I believe that IF "The Beckwiths" is right and the order of children in Richard Marmaduke, Edwin, Malbis and T.W., then the unnamed sons 5 and 6 are Barnes BECKWITH of Spotsylvania Co. VA in 1830-40-50 and William E. BECKWITH of Northumberland Co. VA in 1830.
These seem to be the only two how would fit in the ages allowed? I am not a descendant of this Beckwith line, but I am working on a databse/genealogy trying to trace all US Beckwiths to their immigrant BECKWITH ancestor. Do you have information on descendants of Barnes?