This family seems to have the right combination of names and ages? 1901 RG13/Piece 5015 Folio 57 Page 24 - Ystradyfodwg, @1, Alexander Road
John Evans 44 Head of Household born Carmarthen, Lllanybei: a Coal Hewer
Mary Hannah Evans 45 Wife born Glamorgan, Troedyrhiw
William Evans 25 son born Glam, Ystabfera
David Jas Evans 19 son Carmarthen, Lllanybei
If[v]or Evans 17 son ditto
Samuel Evans 16 son Glam, Rhymney
Gwen Evans 13 dau born Ystradyfodwg
Evan Evans 11 son ditto
Ruth Evans 9 dau ditto
Idris Evans 5 son born Ystradyfodwg
The family are in the area in 1891 - RG12/Piece 4425 Folio 19 Page 40 - Clydach, Ystradyfodwg @ 130, Seely Road. Some other siblings of Gwen are there, that arent on the 1901 census ... all other PoB / Yob as 1901.
John Evans 33 Head
Mary H Evans 34 Wife
William Evans 14 son
Annie Evans 14 dau born Carmarthen, Buttos
David J Evans 10
Ivor Evans 8 son
Lemuel/Samuel Evans 5 son born Ystradyfodwg
Gwen Evans 3 dau ditto
Evan Evans 1 son ditto
John Evans 22 Lodger
David Evans 20 Lodger