Hi Vicki
My grandmother was Sally Ann Shears from Winterslow, Wilts and I frequently come across the Shergold name. I had a quick look to see if the Shears and the Shergolds ever married - probably not.
I did have a look for Robert's marriage and came up with a rather strange result. There are two marriages between Robert and Mary/Marie each on 9 July 1677 but in different parishes.
The entry for Urchfont states Robert s. of Robert Shergoll, and Marie Rivers p. All Canning.
The entry for Stert states Robert Shergoll, the younger of Erchfont & Mary p. Alcanings.
I am confident that these are the same marriage and presumably Robert was from Urchfont. I would guess that the marriage was at Stert and it was also recorded in Robert's home parish.[later information Stert is chapelry of Urchfont]
There is a marriage at Urchfont between Robert Shergoll and Elizabeth Kew 3 Oct 1640, and I assume that these are Robert's parents. My guess is that their first child was Robert 9 Oct 1641 who died, and they named their next son baptized 4 Mar 1644 Robert - it is quite usual to name a subsequent child after a child who has died.
And I was about to post this, but -
there is a baptism at Urchfont 19 Dec 1657 for Robert Shergoll son of Robert living Wedhampton. This seems favourite to be the husband of Mary Rivers, but who was his father ? - this date is outside the dates covered by the IGI.
It is quite conceivable, and not unknown, that this is the third and surviving son named Robert of Robert and Elizabeth.
However, I can find no burials to support the theory of three sons named Robert. The only burials I can find for Robert in Urchfont are 29 Jun 1672, 30 Apr 1679 and 13 Aug 1697; this data base claims to have included Urchfont to before 1600.
I hope you find some of this new and helpful. I think you need to look at the original Urchfont register{on film} to confirm some of these data. In particular to confirm whether the register was readable at the potential date range for burials of the earlier Roberts, and if so, that these burials are absent.
Best wishes,
Colin