Another Welsh lot

[Michael]

... which I'm trying to untangle

1871, Ystradgynlais Lower, RG 10/5434

David Hughes, head, unmarried, 37, quarryman, b Cardigan Llanarth
Eleanor Hughes, mother, married, 70, do
Elizabeth Hughes, sister, unmarried, 40, dressmaker, do
Jenkin Hughes, brother, unmarried, 26, quarryman, do
Eleanor Hughes, daughter, unmarried, 22, dressmaker, do
Thomas Hughes, brother, unmarried, 19, railway navigator, do
William Hughes, brother, unmarried, 14, scholar, do

William is my FMFF - if the census data is to be taken as true then Eleanor senior would be my FMFFM, but since she's 56 years older it seems more likely that she was his grandmother - perhaps Elizabeth was his mother?

Going back a decade...

1861, Llanarth, RG9/4190 (family mistranscribed as "Heher" on Ancestry)

Thomas Hughes, head, married, 50, sexton, b Cardigan Llanarth
Eleanor Hughes, wife, married, 50, [can't read occupation], do
Elizabeth Hughes, daughter, unmarried, 32, [can't read occupation], do
David Hughes, son, unmarried, 30, ag lab, do
Eleanor Hughes, granddaughter, 13, scholar, do
Mary Hughes, daughter, 13, scholar, do
Thomas Hughes, grandson, 9, scholar, do
William Hughes, grandson, 3, do

This time William is listed as Thomas and Eleanor's grandson, so Elizabeth probably was his mother (and by the look of it, Eleanor jnr's and Thomas jnr's as well!).

That's where I've got stuck - haven't found them on earlier censuses, and unsurprisingly there are plenty of William Hugheses being born around 1857-58 so I haven't been able to pinpoint which registration is his. Any help much appreciated!