I am a great-great-great grandson of John McAdoo and Martha Grills. I have corresponded with some of you before, but was unaware until today of the existence of the Grills family genealogy forum.
First, let me say that I do not think there is any substantial doubt that our John Grills was the son of Richard Grills and Sarah Ligon. The record trail from Henrico Co., Va., to Chowan Co., N.C., back to Henrico Co. and on to Albemarle, etc. seems clear. I have referred this matter to Neil D. Thompson of Salt Lake City, who is one of the preeminent professional genealogists in the US if not in the world, and he is, if anything, more emphatic than I am that the descent is clear.
I have a possible candidate for Philadelphia: Philadelphia Elliot, daughter of John and Sarah Elliot, baptised at Shermanbury, Sussex, England, on Jan. 17, 1713.