Just to confuse things it appears there may have been 2 John Wilson's with sons John Stewart,there is a NZ birth for this chap
1879/18534 Wilson John Stewart to Margaret Marion and John
I suspect he may be the chap mentioned in the PP article above
This is the obit for that John Wilson and it may not be your man
http://paperspast.natlib.govt.nz/cgi-bin/paperspast?a=d&cl=search&d=OAM19130325.2.46&srpos=102&e=--1913---1914--100--101-byDA---2john+wilson--There are a lot of children born to John and Ellen Wilson in NZ BDM's
1861/11550 Wilson Agnes Tirizen Ellen John
1863/17466 Wilson Robert William Ellen John
1865/14845 Wilson Mary Ellen John
1865/19832 Wilson Emily Jane Ellen John
1867/24387 Wilson Ellen Ellen John
1867/29988 Wilson Catherine Ellen John
1868/33445 Wilson Ellen Ellen John
1870/26341 Wilson Edward Ellen John
1870/35876 Wilson Alfred Alexander Ellen John
1873/17144 Wilson John Ellen John
1873/19535 Wilson John David Ellen John
1874/28960 Wilson Prunella Ellen John
1874/48452 Wilson Sarah Catherine Ellen John
1876/8762 Wilson Charlotte Ann Ellen John
1881/8041 Wilson Annie Elizabeth Ellen John
1882/283 Wilson Samuel Thomas James Ellen John
1883/1426 Wilson Amanda Mary Harriet Ellen John
Some of the later children may be John Stewart's siblings
Cheers Janette