1937; London, England

For once, Scotland's return home isn't heralded by a loud slamming of the front door which reverberates throughout the entire house – a habit which has necessitated the relocation of the more delicate ornaments England once displayed in their hallway – but Northern Ireland's thin, piercing wail.

It's a sound that strikes Wales hard in some ancient part of his subconscious he had thought long dead, one which sends him flying from his desk without a care for where either his pen or chair falls, a blizzard of paper drifting to the floor in his wake.

By the time he stumbles downstairs, short of breath and heart thudding a rapid, agitated rhythm against his ribcage, Scotland has settled Northern Ireland on one of the sofas in the living room, and is observing him from the other with the sort of trepidation normally reserved for an unexploded bomb. Their faces are a matching shade of red, though only Northern Ireland's is wet, the last of his tears still trickling down his cheeks even though his sobs have died down to soft whimpers and the occasional muculent sniffle.

Wales hunches his body around the sharp pain panic has torn into his side, and braces one hand on the dresser whilst he struggles for sufficient air to gasp out, "What happened?"

Scotland blinks up at him slowly, brow furrowed, as though both the question and Wales' presence are a puzzle he's lacking some essential pieces for and thus struggling to solve. "There was a spot of bother," he says eventually, his gaze drifting back towards Northern Ireland, "at the park."

"What sort of bother?" Wales asks, anxiety undimmed.

Knowing Scotland's penchant for understatement, it could mean anything from a simple tantrum on Northern Ireland's part to a conflagration that has engulfed the rest of the city whilst Wales has been sitting in his bedroom unaware, trying to find the perfect phrase to describe how heavy the sky had looked when he drew back the curtains that morning.

"He got into a fight with another wee lad," Scotland says, drumming his fingers on his thigh. "Hit him over the head with his toy truck, and then they both started bawling."

Wales smiles with relief. If this is simply one of Scotland's usual overreactions to the sight of tears, then it's easily mended. Once their brother retreats again to clear his head – either to the seclusion of his own bedroom or away on yet another walk – as he doubtless will in short order, then Wales will make Northern Ireland a cup of sweet milky tea and reassure him that there's nothing wrong with crying every now and again, because he knows how comforting that would have been to hear when he was younger.

But, before that, there is still the matter of the truck to address. Wales crouches down in front of Northern Ireland so their eyes are almost on a level, and says, "You know you shouldn't hit people, North." It's a lesson that's proving difficult to teach, given the appalling example Scotland and England set in that regard, but one Wales persists with, because it would do much to further family harmony, he's certain, if one more of their number learnt to rely on his words rather than his fists to settle arguments. "I hope you apologised."

"Yes," Northern Ireland says emphatically.

"Good lad," Wales says, giving his little brother's bony shoulder an encouraging squeeze. Almost as an afterthought, he asks, "What were you fighting about, anyway?"

"Right," Scotland says, jumping to his feet, "I'm going to go put the kettle on."

The speed with which he disappears from the room leaves Wales with the suspicion that his offhand enquiry was a foolish one, because for all of Scotland's assertions that nothing frightens him, there are certain situations that he has always proven himself very cowardly in the face of; the kind that might, for example, make Northern Ireland's eyes start to dampen again.

That might provoke him to ask, "Why don't I have a mum?"

Exactly that sort of situation.

Unfortunately, Wales doesn't feel best equipped to handle it, either, because England had always dealt with the weans when their thoughts turned towards the metaphysical – as they invariably did at some point – and he had never had to ask himself. Leaving the question for England to answer on his return from the continent seems like a cruelty, however. A week's far too long to leave Northern Ireland speculating and fretting. At his age, it would probably feel like a lifetime.

They have, however, already had the discussion about death and how it means that a person can't ever come back after the family dog's recent and untimely demise from distemper. To say that their mother is dead isn't exactly a lie, and far simpler for Northern Ireland to digest, Wales thinks, than the truth.

"Not everyone has one," Wales says, warily watching Northern Ireland's face for any warning signs of imminent collapse into fresh upset. "Like Colin in The Secret Garden, remember? He only had Mr Craven."

"Scotland already told me that she's in heaven with Archie, but she went when you were all little boys so she never got to meet me." Northern Ireland's bottom lip does start to tremble slightly, but after biting down hard on it for a moment to still it, he manages to continue with a somewhat shaky: "George said Scotland must be lying because that can't happen."

It's no wonder Scotland always shies away from trying to clarifying this sort of thing if that's the best he can do, and probably explains why most of Wales' own questions of a similar nature were met with a smack to the back of the head and the demand that he keep such thoughts to himself. A simple deflection, always Wales' weapon of choice in difficult conversations, will be impossible now, it appears.

"Well, that might be true for human boys like George, but it's not the case for us, because…" Wales pauses, unsure how to articulate a difference that he's not even been able to figure out to his own satisfaction. It was far simpler when they could imagine that, no matter their primordial origins, they had somehow been created by the ancients in the same way that humans were. Northern Ireland, however, was seemingly born out of nothing more than potentiality and belief as Wales has begun to suspect that, ultimately, all of their kind had been.

If there's anything of their mother in Northern Ireland – and Wales is sure that there is somehow – it's likely little more than the faint wisps of their own memories, bound in tightly with everything else that came together to form him, because he and his siblings had absorbed all else that remained of her in the end.

"Because we're not human," he finishes, somewhat pathetically, when he decides that he'd likely just confuse Northern Ireland with such a vague, half-baked explanation. Anything more complex can wait until he's older. And England's home. "We just work differently."

Northern Ireland's eyebrows scrunch down low over his nose as he digests this equally ambiguous response. "I don't have a dad, either, do I?" he asks after a moment's contemplation.

Wales sighs heavily and shakes his head. If their mother's a conundrum, their father (or indeed fathers) is a problem so intractable that not even Alexander the Great's ingenuity could solve it; Northern Ireland's especially, given how convoluted England's own bloodline may be.

"If it helps," Wales says, "you could think of all of your people as your mums and dads, because they're the ones that made you most of all."

Perhaps. Wales isn't entirely certain of the veracity of that hypothesis either, but it had been a soothing thought for him after Ireland left him behind with Scotland, and all his hopes of maybe experiencing a kinder sort of care as he grew went with her. The wrinkling of Northern Ireland's nose suggests he doesn't care for the idea, though.

Northern Ireland starts to fidget then, jiggling his legs so that his feet thump against the base of the sofa, and biting on his thumbnail (a bad habit he's recently picked up from Wales himself, who's evidently no better a role model than Scotland); clearly agitated, and Wales begins to worry that he's only served to further upset his brother. Maybe he should have lied a little more.

"I know it might be difficult to understand, bach," he says softly, laying a hand on his brother's knee in an attempt to offer him some comfort, "but we're –"

"You are definitely my brothers, aren't you?" Northern Ireland blurts out, his short, skinny fingers wrapping tight and biting around Wales' wrist. "You and Scotland and England?"

That is something Wales knows instinctively he will have to lie about, however, or bend the truth a little, at least. It makes no odds either way, anyhow. It never has.

"Yes," he says. "Of course we are."