Tyllwyd farm in Cadoxton-juxta-Neath Parish in Glamorgan was where Ann Thomas grew up. DOD given as 2/13/1881.

An obituary of her brother David Thomas[1]mentions her as still being alive ("Two of the daughters are still living, one eighty-two years of age living in the parish of Ystradfellte, within a short distance of Colbren Junction, on the Neath and Brecon Railway"), and also she appears in the 1881 census living at Nantyfedwen farm with her daughter Jane and son-in-law William Davies, who was present at Hopkin Hopkins' death there[2]. Why she died at nearby Dolydd farm is not clear - perhaps she had to move from her husband's farm when he died. Perhaps Dolydd belonged to William Hill who was present at her end.
The source of the GEDCOM import plumped for a different Ann Hopkins who died, also in Ystradfellte, in Feb 1881. We are also inclined to doubt the references to the distant settlements of Llantwit Major and Merthyr Tydfil, which we think are the result of arbitrary matching of names that are very common in South Wales. Some families were still using patronymics into the early 1800s, and we think that Hopkins may have called himself Hopkin (ap) Richard in earlier records, as there is a closely-matching marriage record at Cadoxton-juxta-Neath.