I found out where they are buried and wanted to leave everyone on this website who might be reading this the answer.
The cemetery is now not known as Black Friars.BLACKMORE CEMETERY. It is located on Church Hill road near Library, Pa.
From: HISTORY OF UNION TOWNSHIP-SURROUNDING AREA AND THE EARLY SETTLERS. Bicentennial Edition-1976compiled by Noah Thompson 1976
Page103BLACKMORE Samuel Blackmore, Sr., bought 374 acres of land in Peters Township, Washington County in the late 1700's and this plot of land was called "Black Friars." It was left to his son; Samuel Jr. and later years it became the home of the Frank Zimmerman family and still remains in Zimmerman family.Mrs. Zimmerman was a descendant of the Blackmores. Behind the house is the Blackmore family cemetery which dates back as early as 1773.
A big thank you to Ms. J. Will for the information