I have made a study of these early Beckwiths and have loads of documentary information on them. I would be happy to share it with you. Here is the basic information I have on this family.
George Beckwith and Frances Harvey
George Beckwith b. ca. ?1630 ENG md.by 3 Oct 1657St. Mary's Co., MD d.by 19 Apr 1676London, ENG
Frances Harvey b. ca.1641ENG da/Nicholas Harvey & (?) d. 19 Apr 1676Calvert Co., MD
1. Mary b. md. before 1676John Miles (1650 – 1697) s./Tobias Miles & Elizabeth (?) ch:Rebecca, Henry, John, Nicholas, Edward d.
2. Elizabeth b. md. betw.1677-79Elias Nuttall d.
3. Charles b. ca. 1669 Calvert Co., MD (now St. Mary’s) md1 Elizabeth (Hill) Hopewell-Keene md2 9 Oct 1702 Anne (Guither) da/William Guither & Christina Barbara D'Hinyossa Ch:Basil, William, George d. 18 Sep 1712 Prince George's Co., MD
4. Unknown son b. alive 1676 d. a minor
5. Barbara b. alive 1676 md.by 1684 Jacob Seth (Eastern Shore) his 2nd m d.
6. Margarette b. alive 1676 St. Joseph's Manor m.by 2 Apr1688 Michael Taney 1 ch. Margaret (his 2md) Taney prev.ch:Thomas,Michael,John,Elizabeth 2md.ca. 1692 Dr.Joachim Kirsted (d. by 15 Apr 1700) 3md by 15 Apr 1700 George Gray (d.intestate by Jun 1715) ch: John,George,Elizabeth,Ann,& Jane (Elizabeth md. William Meads of Q.A.Co.Jane md. Thomas Smith Jr. d. 9 Jun 1720 will: made 20 Nov 1719 prob: 9 Jun 1720