Joan Mrs Parsons
 

No proof but the details fit:
[Date and place of birth
Names of parents
Date and place of baptism - if applicable
Details of each of his or her marriages - if any James Parsons
Occupation(s) - if any
Addresses where they lived (including county if in UK) - and please list which censuses you have or haven't found him/her on (if s/he lived in census times!).
1776 daughter baptised Hemyock Devon
Date, place and cause of death
Date and place of burial.
Details of will / administration of their estate - if applicable
Memorial inscription - if any
http://genealogistsforum.co.uk/forum...t=mary+parsons

FamilySearch has two other baptisms at Hemyock for children of James and Joan Parsons:
John 2 May 1779 and Anne 30 Dec 1787.

Yes I noticed those also a later marriage for a Joan Parsons. I think precensus family history just requires a leap of faith.

Not necessarily - sometimes if you start building up a possible family tree, you will find something in there that definitely confirms you have the right people, for instance a will mentioning your ancestor.

I notice in Greinton Somerset there is a burial for a Joan Parsons born 1748 but I don't have a subscription. Greinton is where her daughter and grandchildren are buried.