Hi from Australia,
The family you are looking at listed in the 1871 and 1881 Census for Wales, is the family of my great-grandparents, John Mahoney and Catherine Maloney originally from Waterford Ireland.
John and Catherine came out to Australia in 1883 with Dennis (aka Dinah), Mary, Honora (aka Norah), Johanna, and Timothy (my grandfather).
The story in the family was that there were 12 children in all, 6 of whom came out to Australia, and 6 stayed in Wales.
I can only find 5 coming to Australia, one died in Wales before the 1881 Census, and only Patrick and James remaining in Wales.
I don't have any further information on them yet, but will keep this thread in mind if I find anything.
I have a public tree on ancestry called Holmes - Mahoney Queensland if you would like to refer to that for the Australian connection.
Do you have a public tree also that I might refer to?