Alexander Magruder was born about 1700 in Prince George's County, MD There is no documentation on Alexander's birth year. Other sources have dates ranging from 1703 to 1706 to 1715.
Various dates for Alexander's birth have been proposed in different genealogies and 1700 appears most frequently. The date of, about 1706 in Prince George's County appears in the Rootsweb World Connect Project. 
Alexander Magruder was one of five sons ( John, James, William, Alexander and Nathaniel) identified as under 16, and thus born no earlier than 1694, in Samuel Magruder's 1710 will.  Named as a child of Samuel Magruder by Papenfuse.
In his father Samuel's 1710 Will, Alexander is named to receive 100 acres of Good Luck.
Marriage to Ann Wade
Alexander m. Ann Wade, daughter of Robert Wade. Alexander was father of Major Samuel Wade Magruder who m. Lucy Beall, born 1749 to Col. George Beall of Col. Ninian Beall. 
1755 Frederick County Debt Books
In 1755-1756, Alexander Magruder, son of Sam'l, was listed in the Frederick County Debt Books for a 121 acre portion of Magruder's & Beall's Honesty . 
Alexander was named in his mother Sarah's 1731 will.
The Will of an Alexander Magruder was written on 19 May 1749 and probated in Frederick County, Maryland on 18 June 1751; the will names wife Anne and children Nathaniel, Samuel, Ezekiah (Hezekiah), Sarah, Elizabeth, Anna, and Eleanor.
Hezekiah Magruder, son of Alexander and Ann Wade Magruder, was born 1729 in Prince George's County and died Nov 4, 1806 in Montgomery County, Maryland, USA. He married Susannah Talbott (1735 - 1798). They were the parents of Daniel Magruder (1757 - 1842)
↑ Norma Lundgren, My Bunch. Sarah Mills. 24 Jul 2008. 
↑ RootsWeb's World Connect Project. (http://worldconnect.rootsweb.ancestry.com. accessed 8/26/09), Samuel Magruder Quality or Certainty of Data: 3 Note: Submitted by Peter in 2003. Text: Samuel, 1684 - Ninian, 1686 - Elizaabeth CA 1688 - Verlind CA 1690 - Sarah CA 1692 - Sarah CA 1692 - Mary CA 1693 - John 1694 - James 25 Jan 1696 or 97 - william CA 1701 - Eleanor CA 1705 - Alexander CA 1706 - Nathaniel CA 1707.
↑ 3.03.1 Samuel Magruder Will, 23 Nov 1710-31 Dec 171, Prince George's County Will book I Page 46.
↑ Samuel Magruder. Edward C. Papenfuse et al. A Biographical Dictionary of the Maryland Legislature 1635-1789. Volume 426, Page 570 Archives of Maryland online.
↑ 5.05.1 Research of Jack Day, Colonial Maryland Beall Database, 1992-2013
↑ Will of Alexander Magruder, Frederick County, Maryland Liber A-1-11. Viewable online in collection "Maryland Register of Wills Records, 1629-1999," images, FamilySearch accessed 1 November 2015, Frederick > Wills 1744-1777 vol 1 > image 14 of 315; Hall of Records, Annapolis.
↑ Source: #S-2093448485 Note:  Note: Data: Text: Death date: 1751 Death place: Residence date: Residence place: United States APID: 1,2204::346563
Source: S-2093448485 Repository: #R-2142962141 Title: U.S., Sons of the American Revolution Membership Applications, 1889-1970 Author: Ancestry.com Publication: Online publication - Provo, UT, USA: Ancestry.com Operations, Inc., 2011.Original data - Sons of the American Revolution Membership Applications, 1889-1970. Louisville, Kentucky: National Society of the Sons of the American Revolution. Microfilm, 508 rolls Note: APID: 1,2204::0
Source: S-2099802430 Repository: #R-2142962141 Title: U.S. and International Marriage Records, 1560-1900 Author: Yates Publishing Publication: Online publication - Provo, UT, USA: The Generations Network, Inc., 2004.Original data - This unique collection of records was extracted from a variety of sources including family group sheets and electronic databases. Originally, the information was deriv Note: APID: 1,7836::0
WikiTree profile Magruder-43 created through the import of worthington Family Tree.ged on Jun 16, 2012 by JoAnne Worthington. See the  Changes page for the details of edits by JoAnne and others.
Thank you to Ila Barnett for creating WikiTree profile Magruder-68 through the import of Wrenn.ged on Jan 23, 2013.
Click to the Changes page for the details of edits by Ila and others.
It may be possible to confirm family relationships with Alexander by comparing test results with other carriers of his Y-chromosome or his mother's mitochondrial DNA.
Y-chromosome DNA test-takers in his direct paternal line on WikiTree: