Notes:
Data source is the 1990 book, "Moomaw-Mumma-Mumaw-Mumaugh Genealogy" compiled by Robert Austin Moomaw (deceased).
Data source and researcher is Douglas Mumma, 2123 Farmington Place, Livermore, CA 94550
Robert Moomaw reported her birth as 12 Dec 1742 in his 1990 book on the Moomaw/Mumma family, however no evidence or proof for that date can be found and it is probably too early so that date was removed as her birth date.
From her mother's Will, we know that she lived with her parents for six years above her age. From this we would assume that she was about 24 years old when she married Jacob Strickler who is identified in Barbara's father's Will. When Jacob Strickler's first wife had died, he returned to Lancaster County to find a wife. Here he married Magdalena Mumma and they returned to Virginia From his grandson, Adam Strickler's genealogy, written in 1885 (found in "Strickler Families" by Harry M. Strickler 1924, by Harry M. Strickler p 2-4), we learn that Magdalena gave birth to David Strickler who is known as "Col David Strickler" in April 10, 1777. It is not clear if his birth was preceeded by the birth of a sister, Barbara, on 12 Jan 1776. If we assume so, then the marriage likely took place in about 1775.
If we use 1775 as the year of marriage, then Magdalena's birth would have been about 1751.