Hi
An outside possible:
Elizabeth Jones, Catherine's sister, married Thomas Curtis in Pontypridd, March q, 1916. I've found the death of an Elizabeth Curtis, Bridgend, March q, 1970. Her birthdate is given as October 1889
1901 RG13/5065/37/9Banwen, Caegurwen, Llangiwg, Glamorgan (a way from Pontypridd but possible)
John Jones, 35, Colliery Horse Driver, b. Pumpsaint, Carmarthenshire
Lizzie, w, 32, b. Ystalyfera, Glamorgan
Polly, d, 15, housemaid, b. Pumpsaint
Bessie, d, 13, b. do
Annie, d, 12, b. do
Jane, d, 11, b. do
Rosy H, d, 4, b. Brynamman, Glamorgan
Lydia, d, 2, b. do
Catherine L, d, 1, b. do
David Morgans, boarder, 23, colliery horse driver, b. do
Bessie is a diminutive of Elizabeth
This info also fits with later info:
https://familysearch.org/pal:/MM9.1.1/XWXN-BVLhttps://familysearch.org/pal:/MM9.1.1/XWXN-BVTIt might be worth following them on the 1911. Unfortunately, we can't give full information from that census, only info from free index.
Gadget