Thanks again for your message.
I have responded to your message looking for the baptism/birth records of Robert and Patrick Ennis. There I gave you some websites which you may find useful. They will also apply here. One additional link however, is the Irish Times link for parish records. Leixlip is part of Maynooth Roman Catholic parish, to see what is available there follow this link:
If you would like to contact Kildare Genealogy for assistance here are their contact details (fee may apply):
Phone: +353 (0) 45 448350 Email: email@example.com
Some other more general websites which may help you in your research are:
The National Archives of Ireland http://www.nationalarchives.ie/genealogy1/genealogy-records/introduction/
The National Library of Ireland http://www.nli.ie/en/family-history-introduction.aspx
The National Archives UK ? genealogy search: http://www.nationalarchives.gov.uk/records/looking-for-person/
The Public Records Office of Northern Ireland http://www.proni.gov.uk/index/family_history.htm
Genealogy Links Kildare: http://www.genealogylinks.net/uk/ireland/kildare/index.html
Genealogy Links Dublin: http://www.genealogylinks.net/uk/ireland/dublin/index.html
Dublin Heritage: www.dublinheritage.ie
I hope some of these links are helpful. Best of luck.