Hi Teresa,
Perhaps, you could concentrate on the deaths of the fathers, on the marriage certs, does it say if the fathers are deceased? if not, it would hopefully take them into the time of Civil Registration, when you can get the certificates, on them you will have an informer & if it is a member of the family it would give you another lead to go on.
Now I have found on a marriage cert in my own family that the place of residence, was not the place where the family lived, but the place where the groom lived, What was Joseph Henderson's occupation?
Civil registration records are available from the General Register Office (GRO). These start from 1864. You can access the website here:http://www.groireland.ie/research.htm Or you might try Valuations office in Dublin (http://www.valoff.ie) which will have a record of the land registry from 1855 to modern times. This will assist in seeing what happened to any land the familymay have owned (as it usually passed on to a relation).
You could also try contacting the Cavan Co Library for further assistance.
Cavan Genealogy,
1st floor,
Johnston Central Library,
Farnham Street,
Cavan Town,
County Cavan.
Tel: +353 (0)49 4361094
Fax: +353 (0)49 4331494
Email: cavangenealogy@eircom.net
Regards Carmel