Sir William was buried in St Giles Churchyard, Wyddial, East Hertfordshire.
1: He may have died in 1687 or 1688 or even 1686 (see 2: below)
2: A bust of Sir WIlliam and his wife is is here: https://www.flickr.com/photos/52219527@N00/4834674137/ along with this text: "Hertfordshire, Wyddial. 1686 Sir William Goulston died aged 47. The son of Richard Goulston Esq he married Frideswide Morris. Knighted in 1680 he bought the manor of East Bradenham in 1676 from Henry Hungate." Also, "Frideswide Morris wife of Sir William Goulston 1686 , She may have remarried to Sir James Etheridge but died in December 1687." Also "1686 Sir William Goulston and his wife Frideswide (nee Morris) who may have married secondly Sir James Etheridge but if so she did not survive him long being buried in December 1687. William was the son of Richard Goulston, Esq., of Widicot was knighted in 1680 and bought the manor of East Bradenham in 1676. died aged 47. There were 3 children, Frideswide, Mary and Morritius."