I think the 1746 Thomas Richard is the father of Edward Richard(Ystrad Meurig).Thomas probably dies in the early 1750s(though I can't find a confident record).
This is a further reference
Release of the equity of redemption of the properties specified in Nos 220-1 of 28-9 Sept. 1746, and deed declaring ..., 1756, Oct. 28.
Level
File
Summary
1 Jane Morgan of p. Sputty Ystraed Meyrick, co. Card., widow. 2 Edward Richard of the village of Ystrad Meyrick in the said p. gent., son, heir ands administrator of Thomas Richard, late of the said village, yeoman, dec. Release of the equity of redemption of the properties specified in Nos 220-1 of 28-9 Sept. 1746, and deed declaring the uses of the fine specified therein. Witnesses: David Richard's of foes a blyddied, David Williams of Pen y graig, and Thomas Davies of Wernvelen.
This appears to imply a will,which I can't identify either.
Regards
Roger