Ive been thru the Belfast City site trying to find burial records for Edward Booth (thats the name shown on the certified copy death certificate) dod 05/09/1981.
Can find nothing at all, even for just 'Booth' that fits any known family members (he had a son Patrick who died in the 1970's)
The Belfast City Cemetery site only has records from City Cemetery, Dundonald Cemetery & Roselawn Cemetery. I suspect that Milltown is more likely but not all their records are online so it might be an idea to contact them especially if more recent family burials have taken place there. However, I don't think that will take you any further back than Edward himself.
Family stories often have a grain or two of truth even if they get a bit muddled over the years. Possible scenario-
c1871 Lizzie Booth born in England (either as Booth or D'Arcy...)
c1894 Lizzie Booth has daughter Lizzie born Lancashire
1901 Lizzie Booth and son Edward in census in Belfast with daughter Lizzie as a visitor at another address
1905 daughter Lizzie Booth died Belfast
death certificate might give clues- address? informant?1911 son Edward with Annie Gribben in Belfast
has mother Lizzie Booth died, remarried or moved back to EnglandOne reason I suspect that young Lizzie is Lizzie's daughter is that she is also born England (how many English-born Booths can be in Belfast at that time)
If Edward was born to Church of Ireland/England mother but later married a Catholic then there should probably be a baptism record for his conversion in order to marry in a Catholic Church. So, do you know exactly where the 1919 marriage took place?