Searching for Sankey, Gilliland, Adams, Cowden and possibly Graham

Sankeys are from York County and Mifflin county PA.  Some sources say they are Scots Irish and other sources suggest they are English.  I guess there are two branches. 

Gilliland, Adams and Cowden were from  Sir John Fagg's Manor (yes, that is his real name) Londonderry, Chester County, Pennsylvania.

Graham is possibly Alexander Graham son on Aneas Graham of Washington County, Pennsylvania. I know that a family of this surname was from the borders area of Scotland and that there were Grahams in Norther Ireland too.  I am unsure how my Grahams are connected. Have NARA pension file on DeWitt Clinton Graham  son of Alexander Graham, from Monongahela, Washington County, PA.