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I have a few family mysteries yet to solve and this is one conundrum.
I cannot find the resting place of my first cousin Nat Morris and wondering if any members here may have some new searching ideas/leads to try.
Nat died in Newtown, Sydney in 1969 according to his death certificate, and after that the trail goes cold.
Some background in brief which may be helpful. This was not his real name. His government name was Larten Slatopolsky known as 'Nuskie' to the family. and he was born in Glasgow into a Jewish migrant family. He took the gentile name Nathan. 
In the 1920s he absconded from Scotland without telling the family and migrated to Australia where he shortened his forename to Nat and took Morris his father's name as his last name becoming 'Nat Morris.' I haven't found any evidence he changed his name officially or ever naturalized.
In 1931 he married Marjorie May Broughton from an old NSW pastoral family. They had one son Frank who died in childhood at five, so there were no descendants. They lived in Camperdown around the back of Newtown for life.
The family did eventually find out where he was but he excommunicated them essentially. He didn't want anything to do with a reunion of any kind. I have no idea what the reason was behind all of this but something serious must have happened now I think about it. Nobody now knows. I get an inkling from a family story he just didn't want anything to do with being Jewish or his old life for reasons known to himself.
I have searched every cemetery and database I can think of. Including all the Jewish cemeteries.  It was very unusual for someone of a Jewish family not to be interred in consecrated Hebrew ground even if they had left the faith. He's not in Rookwood or Springvale. I think it's clear he was an exception to this general rule. yes I have checked all the name variations, government names, variations, misspellings etc.
Here is where it gets even weirder, Marjorie's resting place ALSO cannot be found! So not just one but two people. I'm wondering if it is possible they were cremations and this was somehow unrecorded or, records are perhaps incomplete, but I think this would be unusual. Were pauper burials unrecorded in NSW state? 
Marjorie's mother had several siblings but amazingly I haven't been able to track any descendants from any; except one branch, her aunt Mabel Alice Audet which also fizzles out. I was hoping someone may have more info but that line of inquiry has been unsuccessful.
Marjorie died 1978 and left her estate to Alfred Alexander Audet the lawyer son of her aunt Mabel. So she died with means, probably owning their house in Camperdown, rather than broke.
After that the trail also goes cold.
It's so odd. I haven't had a case I can't eventually crack yet but this one has me stumped. Thanks in advance.

Associated surnames: MORRIS SLATOPOLSKY ZLOTOPOLSKI BROUGHTON AUDET MELVILLE GIBBONS MCGUIGAN PRICE SAXON

There's a wedding photo for sale on Trade Me New Zealand. I have identified this as the marriage of Leonard William Coker (Cambridge, England 1893 - New Zealand 1971) and Alice Lilian Monk (Pancras, England Mar 1889 - New Zealand 1972). Their marriage was in Blenheim, South Island, New Zealand in 1917. They had one known son Eric John Leonard Coker (1918 - 2008). It’s possible they had other children later. There don't really seem to be any descendants doing genealogy research online so I have edited it and posted it here, on the chance that in the future somebody may come looking and find this image of their ancestors.

https://www.trademe.co.nz/a/marketplace/antiques-collectables/postcards-writing/new-zealand-cities/south-island/listing/3718897416?tm=email&et=41&mt=3B9681F4-EFDD-45D4-BC17-7F5CA3ADC250&bof=eqeasOnK

I am a pretty well versed researcher, I've been working on the family tree for a decade. I'm very aware that my family often changed the spelling of their name and used Barnett, Burnett and sometimes records show Barnet. The Barnett family mostly stuck around the St Cuthberts area for generations. Recently my cousin gave me some old research they'd done on my Scottish Barnett family, years ago saying these were children of my third great grandparents William Barnett and his wife Janet Gray.
I was given the list of names and birth dates below. Well generationally, these would have to be siblings of my fouth great grandfather. He's one of the Williams listed, although what's confusing is he and his wife Janet Gray ALSO had two Williams a year apart in 1818 and 1819. These new names are news to me because I've scoured records and did not find any of this, and still can't.  I am stumped because none of it is coming up in the Scottish government church records, and other databases are turning up nothing. This usually tells me it's wrong and yet, it seems so specific and some of it makes sense...anyone?

Parish register for St. Cuthberts
William Burnett 20.8.1800
James Burnett 16.6.1794
John Burnett 18.9.1795
George Burnett 20.6.1802
William Burnett 16.6.1799
Thomas Burnett 26.10.1797
Joseph Burnett 11.5.1804