Any parent today would weep with worry at the thought of Maud Butler and her brother, Maitland. Who wouldn't have parental sympathy with a mother whose children were determined head to a war?
Maud, who was 18 in 1915 defied the conventional rules of the time about the proper behaviour of girls and decided she would become a soldier.
She cut her hair short and masculine. She bought a uniform, presumably through unofficial channels.
All seemed to be going to plan when she sneaked aboard His Majesty's Australian Transports Ship Suevic. Up the gangway she went when the sentry's back was turned (or perhaps when he turned a blind eye).
She then hid in a lifeboat overnight, only to be discovered in the morning when the ship was well out to sea.
She seems to have been convincing in her disguise as the genuine male military article - apart from in one detail: her boots were black instead of the regulation brown of the Australian Imperial Force. Regular military boots would have been too big so she improvised, tellingly.
And, of course, when she was made to undertake a full medical examination, she failed in more obvious details.
According to her amazing records held in the National Archives of Australia in Canberra, she said she was trying to get to her brother, Maitland, who had already enlisted.
According to the military records, she said there was a parade on the morning of December 24, "when I was discovered and I admitted to the Doctor that I was a girl. My object in stowing away was to get to Egypt to join my brother, Maitland Butler of the 19th Battalion."
But she was mistaken. Her brother hadn't enlisted - or rather, he had, but was then discovered to be underage because his (and her) parents had told the authorities.
You feel for Thomas and Rose Butler, as they must have worried themselves sick with two defiant children with minds of their own, bent on going to war on the other side of the world. Any parent faced with a difficult teenager knows the despair. But two of them - and with a war as the magnet?
Maud didn't give up.
Three months later, after being returned to Sydney, she tried to stow away again, this time by pretending to be a drunken soldier returning to HMAT Star of England (the T is for transport ship). She pretended to be a drunken soldier returning from leave.
She was caught again the next morning, but this time before the ship had left Sydney Harbour. She was put ashore and charged with wrongfully wearing a military uniform. She survived the war and married and lived (presumably) a happy married life thereafter.
Her story is featured in a new book, The Lost Boys, by journalist Paul Byrnes, about the under-age soldiers who fought in the First World War. Maud Butler is the sole exception to the title's subjects.
Among other things, the book gives a flavour of the fervour in Australia at the start of the "war to end all wars".
At the outbreak of the First World War, the number of people volunteering to enlist in the Australian Imperial Force was so high that recruitment officers were forced to turn people away.
As the war went on, casualty rates increased and the number of volunteers declined. By 1916, the AIF faced a shortage of men, and children who had enlisted became a useful way of shaming men who hadn't.
In a recruiting speech in Newcastle in 1916, one Colonel WC Markwell told the crowd he had discovered an 11-year-old boy who had stowed away on a troop ship.
The recruiter, keen to inspire his audience, said the boy had been training for four or five months before sneaking aboard.
"My duty was to send him ashore, but the little fellow was brought aboard the next day rolled up in the blankets.
"I took him to Egypt and the child cried bitterly because I would not allow him to go to the front."
According to the officer, the boy was returned home, "and I had a letter from his mother recently, stating that the boy was quite well".
The drive of the recruitment message was that if boys could enlist, surely adults could. The officer said the boy "was an example for many.
"That young chap wanted to fight for his country and his Empire."
And then the killer line: "Surely there are a few here who could be induced to come forward."
How many children went to war isn't known - by definition, they had to do it surreptitiously, with cunning. Brynes says that towards the end of the war, an Australian officer in Britain was complaining about 400 under-age boys in one consignment - so numbers were high. Byrnes reckons there must have been thousands during the whole war.
In the early years, before the casualty lists arrived back in Australia, the Australian army seemed to be taking under-age recruits when those older than the minimum age were being turned down. Mr Byrnes thinks this may have been because the under-age boys were more "malleable" - they would take orders.
There is a correlation between casualty lists and enthusiasm - as the casualties mounted, enthusiasm to sign up to fight fell.
At the start of the war, enthusiasm was hysterically high.
In The Broken Years, the magisterial account of Australian soldiers in the First World War, Bill Gammage describes the atmosphere in Australia at the start of the conflict:
"Crowds gathered to celebrate, laughing, cheering, and singing, surging with strength and joy and confidence.
"At Labor Party headquarters, at Melbourne University, and on a Queensland cattle station men sang 'Rule Britannia' and the National Anthem after work.
"Children sold pets, school prizes, and the treasures of a lifetime to help patriotic causes. Strangers embraced as brothers, cheers were given on the slightest pretext, flags waved frantically, tumult and merriment ruled everywhere."
In this atmosphere, who could resist the pressure piled on by the pipers?
They trumpeted the efforts of the far-too-young to go to war. There were the cases of John Smith who enlisted at the age of 15 and Frank Day who went at the age of 11 (who may have been the 11-year-old boy mentioned by the recruiter).
John Smith apparently had shimmied up a rope to get on the troop ship at Port Melbourne.
"I thought I would like to have a trip with the boys as a lot of my cobbers had gone," he told the Melbourne Herald.
"I knew I was too young to enlist, for I was not a turnip altogether, but when the troops were being sent I made up my mind to go as far as I could with them."
He got as far as Cairo where he was given a uniform and worked in the safety of the mess far from the fighting (but still, you might think, far too close for a child to be and far too far from his parents).
Some mothers tried to keep their children safely at home, but then relented.
The book cites the case of Private Roy Norman Tucker, who enlisted at the age of 15 years and 10 months.
The Sydney Daily Telegraph ran a story about him after he was wounded at Gallipoli. His mother said she had tried to stop him going to war but "the great determination and pride which he showed swayed us. I am sending along the boy's photo in the hope that publication might serve as a pattern to others".
It is true that the idea of age was different then. Remember that childhood lasted until the age of 11, after which began a working life for many.
Frank Day, for example, had already been working for a year when he stowed away at eleven, according to Byrnes.
"There was also a common belief that boys and girls 'in the colonies' grew up faster and were more physically developed than their counterparts in Britain," Byrnes writes.
The celebrated war correspondent Charles Bean, who went to school in England, echoed that thought when he said young Australians learnt much about soldiering from the time they spent in the bush.
Having said that, there were some doctors who baulked at sending a child to the fields of slaughter, particularly as the true nature of the war became known and the casualties were returning (or not returning).
Determined child soldiers needed increasing cunning. A failure to dupe the authorities in one town might succeed in the next.
And there was a loophole. Boys younger than 19 could enlist as buglers provided they had the written consent of their parents.
"This explains the number of under-age boys listed as buglers - often in their death notices," Byrnes says.
In contrast to the gung-ho jingoism of the papers at the time, the stories of children at war read like a tragedy now.
As the war ground on in mud and blood and tears, attitudes in Australia changed. The army changed its policy towards young warriors.
By 1918, ships were returning with boys who should never have gone in the first place. To add insult to the injury, these boys had their pay docked for inconveniencing the military which they had striven to serve.
We may weep for them now.
"Some died in battle, some in hospitals and casualty clearing stations," writes Byrnes.
"Some were wounded, healed and wounded again before they were killed.
"Some were patched up and sent home minus an arm or a leg, or with lungs damaged by gas.
Some were sent home because they were under-age. Some have graves, many do not."