Andrew Allan was a prospector and miner, and was often away from home.
Jim was a boxer and footballer, and attended Thames High School where he excelled in English literature.
The family were not well-off; in the month that Jim enlisted, his mother applied for charitable aid.
Jim was assigned to the 1st Canterbury Infantry Battalion and arrived at Gallipoli in August 1915, taking part in the battle of Suvla Bay before joining the operation at Anzac Cove.
After two weeks he was sent to England to be treated for dysentery at a hospital set up in the pavilion of Manchester's famous Old Trafford cricket ground, where he was visited by a cousin and taken to meet more relatives in the town of Biggar in Lancashire.
Jim sailed to rejoin his force in Egypt but was put ashore in Malta as he had contracted scarlet fever. A letter to his family from this time conveys how happy he is to have received their letters and a care package - with socks, scented soap, sweets and cigarettes - that morning.
"The letters I received today were the first news of my dear ones. I was rather surprised to hear of Willie's wedding. I think it will be a few years before anyone hears of my wedding."
Another page addresses his younger sisters, Violet and Iris: "To the dearest girls in the dearest town in the dearest country on earth".
"I hear ... that Vi is working at a bookbinders. Some kid, now isn't she Iris. Keep well girls and look pretty when I come home and with my dearest love and kisses, Your brother, Jim."
The young New Zealander eventually rejoined his battalion at Armentiere, France. He took part in the battle of the Somme and was wounded on September 16, 1916.
The Anzacs suffered huge loss of life the previous day.
Jim was admitted to a hospital at Etaples with gunshot wounds to the shoulder and legs. He died there on September 23, only 12 days before his 21st birthday.
His relatives still treasure memorials sent to his mother from the Government and others, including a card showing his grave and medals.
Much is known about the names engraved at the base of Lion Rock thanks to the research efforts of Sandra Coney, the former campaigning journalist and now chair of the Waitakere Ranges Local Board.
Ms Coney, whose family have a long association with Piha, said the plaque's list of names contained inaccuracies, with some listed as dead having survived, and some names missing.
Neil Matheson was on the list of dead and used to tell his friends to read the plaque with him if they wanted to see a dead man walking.
The mill closed in 1921, and many of the war veterans went to work in the forests at Mamaku.
100 Kiwi Stories runs every Monday and Thursday.
