"He was such a fine lad -- it was hard to see him just slip from us," wrote J. Todd, sister, who tended to him at the No 8 Casualty Clearing Station after he suffered shrapnel wounds when he was hit at Armentieres near Ypres.
"Your son Pte Elderton of 1st Canterbury New Zealand Regiment was admitted to this hosp on the 9th suffering from shrapnel wounds of the abdomen," she wrote in July, 1916.
"He was operated on at once and the damage to the bowel repaired as far as possible.
"After coming around from the anesthetic he became restless at times and had an anxious look. He did not have a good time & yesterday morning looked much worse. He lingered on until 2pm.
"I am deeply sorry to be the bearer of such tragic news & to have so very little to tell except the bare facts. I hope you may hear from someone in his regiment."
Elderton kept a diary, and just a year before he died, on May 30, 1915, he wrote to his brother about training at Trentham near Wellington.
"It is a devil of a big camp," he said.
In October that year, he left New Zealand, arriving in Egypt which did not impress him.
"It [Cairo] is a hell of a place," he wrote.
The intensity of training increased and he went to "a big camp near the canal and not far from the trenches ... undergoing some pretty severe training".
In May he sailed with the rest of his division for France and after landing at Marseilles, he headed for Armentieres where he fell.
His last diary entry was on May 29, when he wrote of a shell burst which killed one and wounded several others.
His final letter was to his brother, Frederick on June 30, 1916 when he wrote "the weather is very broken and it makes things very miserable in the trench when you are wet through, for you never undress and you don't have a change of clothes."
He lies buried at Bailleul near where he died.
• Arthur Elderton was the author's great-great-uncle.
