Here are some willsthat mention the surname Willcockson and Boone, so I'm including them in case there are clues for you.
(this has Boone and wilcockson)
BOONE, JOHN, Exeter.Berks Co October 5, 1785 - October 22, 1785.B - 128. Bond held against nephew Judah BOONE for £199-12-2 to be divided between him and his brother Moses.To nephew James BOONE walnut chest, rifle, etc., also £100 due on bond of William HUGHES.To Martha wife of George HUGHES, £20, remainder of said bond.To Rachel wife of William WILCOCKSON, bond of Samuel BOONE for £105.Bond of Isaiah BOONE for £184 divided as follows:£50 to Anna wife of Abraham LINCOLN, £50 to Mary wife of Thomas LEE, £20 to Mary HUGHES and remainder to said Isaiah BOONE. To nephew Joshua BOONE a bond of William SCHOEFIELD for £7-10, also his own bond for £50. Mentions having learned "from my countryman Anthony HOLMEAD that the sheriff of Frederick County, MD, has a demand against me and directs said HOLMEAD to pay the same out of money he owes me."Exrs:James and Joshua BOONE.Exrs: Daniel SCHNEIDER, Jonathan MEE, and Thomas CHERINGTON.
Chester Co. WILCOCKSENF GEORGE. October 25, 1739. Adm. to Elizabeth Wilcocksen.
WILCOCKSON, ELIZABETH. April 17, 1740. Adm. to Philip Yarnall.
This may be who your friend was speaking of.there is no will but there are adm papers on file....have you gotten copies of the adm papers?There may be something of interest....and, there seems to be a Yarnall tie in this generation, too, as Philip is the adm. of Elizabeth's estate.