I can put you in touch with someone who did a lot of research in Avoca and had some Leeson relations. If you go back through all these messages off and on Leeson information has been posted.www.familysearch.org
PILOT: FOUND UNDER SEARCH RECORDS on the mail page of
family search, and has 1864 + records to about 1950's.
Lots of information there with wives and children's names.
There are 6 listing in www.eircomphonebook.ie
2 in Aughrim
(closest) and 1 in Roundwood) I think if you wrote a form letter to all of them with what you know of the family you want information about you will probably get some answers.
No postal costs required outside Dublin and the eircom address sufficient for delivery.
On the Civil Registration CD of the LDS are 5 Leeson births but wives are either Charlote or Catherine.
1 William born Jan 1, 1868
William Frederick marriage to Eliza Mary Westlake 23 Feb 1847, Glenealy. Fa: Robert Leeson Fa: John Westlake
'genealogy for fun'