Hi
I see the family on the 1891 census
Rg12/4450/81/12
3 Olive Terr Llan Village Llangymyd Bridgend Glam
Isaiah Jones head b 1860 Wednesbury Staffs collier
Harriet wife b 1862 Dudley Worcestershire
William G son b 1881 Dudley ..
sarah J b 188 Dudley ..
Isaiah Jones b 1888 Tredegar MonmouthshireI see the family in 1881 in Dudley Rg11 2865/84/11
I noticed Isaiah works in the iron works .
cheers cardiff
look at this siteit does not give you your answer but will give you a few bits of info
http://thomasgenweb.com