I can see a death for Eileen Davey on 25.5.1964 in Lisburn aged 36 which seems to fit with your information. You can view the original certificate on-line on the GRONI website, using the “search registrations” option:
https://geni.nidirect.gov.uk You will need to open an account and buy some credits. It costs £2.50 (sterling) to a view a certificate.
Eileen’s marriage isn't on-line but you can get a copy of the certificate if you want. Likewise Eileen was evidently born around 1928/29. Births in Northern Ireland within the past 100 years, marriages within the past 75 and deaths within the past 50 aren’t searchable on-line. They are open to the public, just not on-line. If you know all the key details eg exact date and place of birth, parents names etc, you can order a copy of a certificate from GRONI for £15.
https://geni.nidirect.gov.uk But if you don’t have all the information, you need to get in touch with them to get a search done. They will do a 5 year search for £7 and if they find a matching certificate you can purchase it for £8, coming to a total of £15. It will be posted to you a few days later. You pay over the phone using a credit card. You type your number in on the phone keypad. They don’t know what it is. They won’t deal with these searches and orders by e-mail because they need you to type the credit card number in yourself.
Phone: 0300 200 7890 (+44 300 200 7890 from outside the UK).
If you get both Eileen’s parents names and post the information here we can search for a marriage and backwards for their families.
