Hi Red Kite.
Further info is that my Watts family Thomas and Susannah Watts farmed at Ty Llwyd, St Georges, not sure if this was Castle Farm but my Grandmother Florence was born at Castle Farm in 1888. Other children were Mary, Rachel, Edward, John, Norah, Fanny born between 1883 and 1892. I visited it as a child with her to be introduced to the Great Aunts but have to admit to being more interested in the GWR line which ran alongside! There is also a connection to Sant Tylyll (or St-y-Nyll) a (now demolished) large house at St Brides-super-Ely through my great-great grandfather Edward Watts. One earlier posting from 'Dragonsheep' mentioned St-y-Nyll, Edward Watts and Thomas Llewellyn (my second cousin, son of Norah Watts) so we are clearly on common ground! My great Grandmother at Castle Farm was a Williams who was descended from Thomas Williams a Welsh hymn writer who built Bethesda Fro Chapel at St Athan. I have no information regarding any connection to the Morgan line.
Regards