Marriages contain the date, parties names, ages (usually full or minor, but occasionally actual ages) previous marital status, occupation, residence at the time of the marriage, fathers name and occupation. Also the location of the ceremony and the denomination; the name of the person conducting the ceremony and 2 witnesses signatures.
A death has the date and location; name; sex; marital status; age; occupation; cause of death and whether certified by a doctor; name and address of the informant; date of registration.
So you should get some of the information you are after. No mothers names on Irish (or English) marriage certificates.
You can view the original certificates on-line on the GRONI website, using the “search registrations” option:
https://geni.nidirect.gov.ukYou will need to open an account and buy some credits. It costs £2.50 (sterling) to a view a certificate.
