It's the kind of war romance you don't usually hear about - two New Zealand soldiers who fought side by side in World War I and fell in love with each other.

Their relationship, forged on the French battlefields, held true for the rest of their lives.

When machine gunner Norman Gibson was seriously injured in the Somme, his confidante, Roy Ayling, didn't know if he'd live or die.

So Mr Ayling penned a poem to express his grief for the man he called his "Old Sunshine".

Mr Gibson's daughter, Miriam Saphira, is now the only one left to share their remarkable love story.

"They met up quite early on in France and were together all the time in the Somme," she said.

"It was love, I think, really. I think they loved each other."

Both survived World War I and purchased a farm in Taranaki. They lived together for 13 years and shared a double bed.

"The two men were quite wise. They mixed a lot with the Miss Mortons down the road," Ms Saphira said.

"They were sisters and were not interested in marriage or anything else. They could go out together so it would look like they were hooked up, so to speak, for the gossipy people up the road, so that was probably pretty good cover for them."

But under pressure from Mr Gibson's father for him to find a wife and have a family, the two lovers were forced apart.

"Roy was absolutely devastated when they broke up," Ms Saphira said.

Mr Gibson would have children, including Ms Saphira, but he never stopped seeing Mr Ayling - something Ms Saphira says her mum came to terms with.

"It was just accepted that they had lived together and were very close and so on. My father saw Roy every week," she said.

"The fact that they kept on - the love, the bond was still strong. They kept in contact all of Roy's life, until he died."

Mr Aylin's death came in 1952 and, as Ms Saphira remembers, her father dealt with the grief in way perhaps typical for rural men of the time.

"He wasn't one who expressed his feelings very well at all. I think he probably stomped over the back of the farm and cut out more gorse."

It was a romance that endured through war and peace, and even Mr Gibson's marriage to another.

It's one that lives on in the memory of Ms Saphira, and the words Mr Ayling wrote for his man, Norman.

Newshub.