Hello...
No actual help sorry, just some thoughts.
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It may be worth getting the birth printout for Letitia's youngest son
Thanks for the tip Janette but it would only be helpful if the grandparents were shown on the death register
I think the reasoning behind Janette's suggestion is that the 1889 birth certificate for Letitia's youngest son should hopefully mention Letitia's birthplace. In an earlier thread you mention that Mary MURPHY was born in Melbourne so if Letitia was also born in Melbourne it's a link, albeit fairly tenuous. You could then purchase Letitia's NZ death certificate which hopefully mentions her parents. Then find the parents (hopefully in Melbourne c.1850) and fingers crossed they have a daughter Mary/Martha born 1851-ish
I know what you're thinking :-) It would be more direct (and cheaper) to just purchase Letitia's 1890 death certificate but her son's 1889 birth certificate is more likely to have an accurate birthplace for Letitia. Presumably she would have been the informant.
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Would the marriage certificates [for Mary and Letitia] have any more details
Before purchasing marriage certificates it might pay to ask for a kind Rootschatter to do ITM lookups. One for Mary (1867) and two for Letitia (1867 and 1868). No guarantee they'll be of any help but you never know.
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Mary married my great grandpa, Thomas Minton, on 6th May 1867 at Brighton (south of Dunedin)
As Lucy reasoned in a previous thread, it's more likely to be the long-gone gold-mining town of Brighton a.k.a Tiromoana on the West Coast of the South Island, not the Brighton south of Dunedn.
In the late 1860's Brighton/Tiromoana was home to five thousand feverish gold miners, one of which was presumably your Thomas MINTON, and fifty-three pubs, one of which was presumably the Empire.
Regards
Beg