Not able to do address search - but came up with census info
1901 census
RG13/5003
Reg district: Pontypridd. Sub-reg: Llanwonno
Folio: 85 Page: 19
Address 102 Roberts Street, Ynysybwl
Daniel Roberts abt 1846 Burry Port, Carmarthenshire, Head Llanwonno Glamorgan (coal miner)
Mary Roberts abt 1846 Burry Port, Carmarthenshire, Wife
Sarah H Roberts abt 1882 Treorchy, Glam Daughter (draper's Assistant)
Mary Roberts abt 1888 Ynysybwl, Glam Daughter
Checked all of Robert Street 1901. Number 151 is vacant
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1891 census
RG12/4414
Llanwonno
Folio: 76 Page: 19
Address 91 Roberts Street.
Roberts, Daniel abt 1846 Pembrey, Carmarthenshire, Head Llanwonno Glamorgan (coal miner)
Roberts, Mary abt 1847 Pembrey Carmarthenshire, Wife
Roberts, David abt 1875 Capcoch ? Aberdare, Son (coal miner)
Roberts, Gwilym abt 1873 Capcoch ? Aberdare, Son (coal miner)
Roberts, Mary A abt 1877 Pentre Ystradyfodwg, Daughter
Roberts, Sarah H abt 1882, Treorchy Glamorgan, Daughter (scholar)
Roberts, Maggie abt 1888 Ynysybwl, Glamorgan Daughter
Richards, Gwilym abt 1879 Pembrey, Carmarthenshire, Boarder (coal miner)
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1881 census
RG11/5301
Reg district: Pontypridd
Ystradyfodwg (old name for the Rhondda Valley)
Folio: 117 Pg 32
Address: All at 187 High Street, Ystradyfodwg, Glamorgan (There is a High Street in Treorchy, Rhondda)
Daniel Roberts abt 1846 Pembrey, Carmarthenshire Head (coal hewer)
Mary Roberts abt 1845 Pembrey, Carmarthenshire, Wife
David Roberts abt 1875 Aberdare, Son (scholar)
Gwilym Roberts abt 1873 Aberdare, Son (scholar)
Mary A. Roberts abt 1877 Ystradyfodwg, Daughter
John Roberts abt 1866 Pembrey, Carmarthenshire, Boarder (coal hewer)
Samuel Roberts abt 1855 Pembrey, Carmarthenshire, Boarder (coal hewer)
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Do you have any more info on William John Richard and family to try and trace them?