Wilhelm "William" Younkin was born on April 22, 1805 in Lovettsville, Loudoun County, VA, the son of Jacob "of John" and Eleanor (Chambers) Younkin
As an infant, he was baptized in the Reformed Congregation of Loudoun County, and his sponsors included Christoph Barnhaus and Rosina (?).
He married Catherine Firestone ( ? - ? ), daughter of John and Margaret (Thrasher) Firestone who were natives of Virginia and also were pioneer settlers of Ursina, Somerset County, having arrived circa 1802. John's father Johann Nicholas Firestone, a German immigrant from Alsace, was a veteran of the American Revolution, and grandparents Hans Nicholas and Catharina (Nunnemacher) Firestone brought the family to America aboard the Peggy, arriving in Philadelphia on Sept. 24, 1753.
Catherine's known siblings were Joseph Firestone, Jacob Firestone, John Firestone, George Firestone (who married Catherine Younkin), Mary May, Elizabeth Miller and Margaret Leighliter.
William and Catherine produced two known sons, born between 1827 and 1836 -- John X. Younkin and William Younkin.
Sadly, William died in or before 1851, and likely in the early 1840s. In 1851, when his late father's estate was settled, William was no longer living, and his sons as heirs each received payments of $10.72 from the estate. His son John was said to have been raised by grandparents, likely the Firestones (but this needs to be confirmed).
Catherine died sometime before 1852, and maybe much earlier.
When William's father in law John Firestone wrote a last will and testament on May 1, 1852, both William and Catherine were deceased. In the document, he listed his living offspring and stipulated that his grandsons William and John were to receive assets from the estate, with William to have one-eighth share of the bequeathed property.
Nothing more about this couple is known.