As far as I know Edward Richard died unmarried and I can't find any evidence that his brother who died relatively young married either.I can't see any reference to sisters-so the only hope of finding a relationship with John and James(even if we confidently knew their parents) would be through Edward's parents,which seems a difficult prospect.
The only snippet I can find,which is slightly mysterious,assuming it is correct,is the following,which refers to a David Thomas "heir at law"(again assuming the correct Edward Richard).
Indenture, being a lease for a year (so that a grant by release might be made) from John Rice of Llandovery, co. Carm., yeoman (eldest son of David Rice of p. Llanavan, co. Card., dec., who was the eldest son of Hugh Rice of p. Lledrod, co. Card., clerk, dec.), Thomas David of p. Llanilar, co. Card., yeoman (eldest son of David Morgan of p. Sputty Ystrad Meirick, co. Card., gent., dec., by Catherine his wife, dec.), David Thomas of p. Sputty Ystrad Meirick, yeoman (heir at law of Edward Richard of same p., gent., dec.), Elizabeth Davies of p. Lledrod, co. Card., widow, and Richard Davies of p. Llanvihangel Lledrod, gent. (brother of William Davies of Penbrynn in same p., gent.) to Rev. David Williams, clerk, curate of Eglwys Newydd, co. Card., of a parcel of land called Gwar-y-fordd-las (8 a.), being part of a tmt called Bryn-merllyd, also parcels of land called Cae-gwyrglawdd-tan-y-fordd-las (8 a.), Cae-penddolwen-cae-issa (12 a.) and one-third part of a piece of bog land (60 a.) called Gorse-glan-teify, being parcels of a tmt called Pen-brin-merllyd, all being in p. Llanvihangel Lledrod, co. Card., but reserving to the said William Davies a right of turbary. Consideration, £200.
The phrase "heir at law" as far as I can tell implies a right through a blood relationship in the case of intestacy.
This is odd because there is a will for Edward in 1777,which makes no mention of David Thomas.The timing of various events is interesting.The will is written in February,Edward dies in March,the will is registered in April,the indentures are dated May and the probate is granted in June.
Perhaps,in my favourite phrase from Rootschat,this is a red herring barking up the wrong tree.
I wonder who David Thomas was?Sounds like he could be a patronymic son of Thomas(Richard?),(therefore ,otherewise,David Richard?)
Regards
Roger
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