Unknown father of Ernest Arthur MOODY from Denise Moody in an email dated 16 October 2017.
Denise is the wife of Robin Moody. Robin’s father, Ernest Arthur Moody, was adopted. Ernest was born James Campbell Lumsden ROBERTSON, his biological mother being Gertrude Eleanor Robertson (b.1887), father may this James Campbell LUMSDEN. Gertrude later married Lionel Ernest Carrel (b.ca1885).

There is a thought, in an email dated 22 October 2017 from Denise Moody, that the father of Ernest Arthur MOODY may have been James Campbell LUMSDEN. This has yet to be verified.

In a subsquent email dated 20 July 2018 from Denise Moody:
“We think a man called James Campbell LUMSDEN was Ernie's father, he was in Dunedin at the right time… [family resemblances mentioned]”.
“James Campbell LUMSDEN was actually born James Lumsden CAMPBELL to a Miss Mary Campbell and she never married”.

In a followup email dated 22 July 2018, Denise writes:
I wouldn't say I was 100% sure that James Campbell Lumsden was Ernie's father but I would say I am 99% sure”.
“At the time Ernie was conceived, James was living at 9 Market Street, [Dunedin]… It must have been a boarding house when James lived there and wasn't too far from where he worked at the Phoenix Flour Mill. It was a very big old wooden villa and when it was turned into Quendon Private Maternity Hospital they must have bought the villa next door as well and joined them together. It is long pulled down and town houses put up”.
“Gertrude Robertson lived in Mornington at the same time and it would be just a short tram ride from Market Street to where she lived, she was not living with her parents at the time, both were unmarried…”
“Mary Campbell was the Mother of James Lumsden Campbell as he was known at birth. Then, at about age 2, he became James Campbell Lumsden, but she was still Miss Mary Campbell when she died, and she was sent James’ WW1 medals so know we have the right person. On James birth certificate it says illegitimate with Mary Campbell as Mother and Father unknown”.

Year of death registration from Death search on New Zealand BDM website in July 2018:
1918/44834. Lumsden, James Campbell, died age 27Y

Full date of birth from further searching on BDM Search by incrementally changing the date range for the birth, Brian of nzolivers has determined date of birth as 16 June 1917. Brian wonders that if he was aged 27 at his time of death, he would of been born circa 1890.

Date of death confirmed:
http://www.aucklandmuseum.com/war-memorial/online-cenotaph/record/C9009
James Campbell Lumsden
Unknown date of birth - Died 16 June 1917
SERVICE NUMBER: 22343 AWMM
ARMED FORCE / BRANCH: Army AWMM
LAST RANK: WW1 Private AWMM , Otago Infantry Regiment, 2nd Battalion AWMM
WAR: World War I, 1914-1918 AWMM

James Campbell Lumsden
https://www.nzwargraves.org.nz/casualties/james-campbell-lumsden
Secondary Memorial: Waianakarua Memorial Hall
Conflict: WW1
Additional Information: Son of Mrs. Mary Campbell, of North Blackboy, Tulloch, Old Meldrum, Aberdeen, Scotland.
Service Number: 22343
Rank: Private
Date of Birth: Not known
Next of Kin: C.S. Morris (friend), Waianakarua, Otago, New Zealand
Date of Enlistment: Not known
Occupation on Enlistment: Flour-miller
Armed Force: Army
Unit:NZEF, Otago Regiment, 2 Battalion

100 Kiwi Stories of WW1: Living memorial to the fallen
https://www.nzherald.co.nz/nz/news/article.cfm?c_id=1&objectid=11310230
The trees, with plaques, and latterly crosses, are on many Oamaru streets. Where possible, they were planted close to where the dead were from - at entrances to farms, outside houses, or in the case of James Campbell Lumsden, outside their place of work.
Scottish-born Lumsden was working as a flour miller at Dunedin-based Phoenix Company's Waianakarua mill, 22km south of Oamaru, when war broke out.
He left New Zealand in August 1916 and was serving with the Otago Infantry Regiment, 2nd Battalion, when he was killed "in the field, France or Belgium" on June 16, 1917. He was 28.
Lumsden is buried at Messines Ridge British Cemetery in Belgium but an English oak, planted in 1921 at the State Highway 1 roadside, just 100m from the old mill, stands testament to his sacrifice.

In a further email dated 21 November 2018, Denise writes:
“We now have DNA evidence that he [James Campbell LUMSDEN] was Robin's [Robin Ernest MOODY] Grandfather. James Campbell Lumsdens Grandparents were Margaret (nee French) and Andrew Campbell, they actually bought up James”.

Fulll date and place of birth, place of death, from Denise Moody in her “Denise Brightwell Family Tree” in November 2018.