The baptism for Thomas Morgan in 1898 could well be 28/3/1898 at Begelly church, son of Thomas and Catherine Morgan, collier, of Williamston.
If I am right, the father was the son of David Morgan of Oats Hay, Williamston.
I have an interest in the extended Nash family around the Saundersfoot and Begelly area. In my early family research in the 1980s, by chance I visited two Nash ladies, one of whom was unmarried if memory serves me right, living at Laverock. I remember with much fondness spending spending a couple of hours or so chatting about how we could be connected but without finding the link.