I am not related to your ancestry, but looked up some data in a few books.
"Virginia In 1760: A Reconstructed Census" by T.L.C. Genealogy lists;
Sykes, William Prince George 43:161 (Prince George County, Va., Wills, Deeds, Etc. 1759-1760 LVA Reel 2 (Library of Virginia)
"Virginia In 1740: A Reconstructed Census" T.l.C.Genealogy
Sykes, Bernard Prince George 087 (Prince George Co. Minute Book, 1737-1740
Sykes, John Prince George 087 (Prince George Co. Minute Book, 1737-1740.
There were no Sykes listings for the 1720 Reconstructed Census book.
"Prince George Co. , Va. Wills and deeds 1713-1728" abstracted by Benjamin B. Wesiger, III 1973 has Sykes listings for Bernard, Frances, John and Richard.
P.31 Inventory and appraisal of Bernard Sykes' estate Aug. 5, 1718 Value L 39/10/4 presented by Bernard Sykes, admin'r Recorded 12 august 1718.
P.34 Appraisal of the remainder of Bernard Sykes' estate L 2/10/0 by Gib. Hay, James Harrison, William Harrison 9 Dec. 1718 Presented in court by Bernard Sykes, Adminr.
P.35 Accounts of Bernard Sykes; estate for 1718 13 Jan. 1718 Mentions Richard Cureton, Joseph Clarke.
P.108 June 14, 1725 John Sykes and Frances his wife of Pr. Geo. Co., to Bernard Sykes of same, land on N. side of Blackwater Swamp in Martins Brandon Parish, 100 acres, Part of a tract granted to Robert Lucy, deceased, by patent 3 Nov. 1673; bounded by Cattail Sw., William Harris, and John Sykes.
Witnesses; George Hamilton, Jr., Richard Sykes, Eliza (X) Simmons Recorded 13 July 1725 signed John Sykes and Frances Sykes..
4 April 1728 Abraham Odium to Bernard Sykes of Pr. Geo. Co. land in Martins Brandon Parish on west side of old Town Run, bounded on north by land of Phillip Jane, deceased, east by land of Edward Hill, deceased, and south by the main woods and Land of Richard Pace, 100 acres, for L 21; said parcel was formerly purchased of John Jean by Thomas Anderson, and by Anderson given by will to Mary, his relict, during her life and afterward to his eldest son James Anderson, and by Cornelius Cargill and Mary his wife (aforesaid relict of Thomas Anderson) and by James Anderson sold to Edward Goodrich, recorded in Pr. Geo. by deed Jan. 12, 1713. By Goodrich in his will recorded Jan. 10, 1720. Witnesses: William Binford, Timothy Rives, Richard Flewelling, signed Abr. Odium, Sarah Odium April 9, 1728 Sarah, wife of Abraham Odium, relinquished dower rights.
P. 73 10 Feb. 1722 John Sykes and Frances his wife of Pr. Geo. co. to Nathaniel Harrison, Esq. of Surry co., 60 acres in the church Old Fields at a place called Martins Brandon in Martins Brandon Parish. Said land is land Anthony Wyatt was seized of by right of Elizabeth, his wife, who had an estate of inheritance in fee simple in the said land and which afterward descended to John Wyatt as heir at law of said Elizabeth, who dying seized thereof, it descended to his three sisters, as heirs at law to him, which land divided into several parts and the lower part alloted to the said Frances, one of the sisters thereof. Witnesses; Thomas Eldridge, Thomas Griffiths, William Gary, recorded Feb. 12, 1722 signed John Sykes and Frances Sykes.
I usually do not answer queries any more and do not do lookups since my personal reference books are limited. I also have a small amount of time in which to copy and send data to anyone anymore.
I hope that some of this helps you in your search.