Having been responsible for bringing down an ancient evil would be cause for anypony to feel smug, and for Rainbow Dash, she felt doubly so. After all, she was a national hero now, and alongside her friends, she had made things pretty awesome. As for said friends, they all watched with bemused expressions as their cyan companion went on and on about how much she loved their adventure in the Everfree Forest together. It was a lovely day in Ponyville, and the five of them were busy spending it at the local café, each slurping down their respective milkshakes. Despite the hectic goings on of the Summer Sun Celebration, life in Ponyville had more or less gone back to the calm normality it had known before that unexpectedly eventful night. But for Rainbow, there was still so much to talk about.
"And then Rarity?! You were, like, super-brave going right up to that serpent like that! You totally knew how to get past him!"
Rarity waved her off.
"Oh please, darling! It's all in a day's work," she responded humbly.
Rainbow cackled, taking a good gulp of her milkshake before getting back to her friends.
"I tell ya, that quest was the best thing that ever happened to us! Coz I dunno about the rest of you, but things in this town were getting kinda boring before that!"
Fluttershy looked to her childhood friend meekly.
"Um...I sort of liked it that way."
Rainbow softened to her, patting her on the shoulder.
"Hey, nopony ever said it always had to be that way, Flutters. I'm sure you'll get plenty of calm and quiet days after this."
Fluttershy smiled to her friend's words, but rather than respond herself, it was Applejack who did the honours.
"Ah tell ya, that Twilight girl certainly knows how ta make an entrance!"
Pinkie, who had finally finished her milkshake, and of course finished it before everypony else, looked up and scoured the immediate area.
"Oh yeah, where is Twilight anyway?"
Rarity turned to her.
"I believe she had a few chores to do. Groceries, I think."
"Ah, there she is!" Applejack called.
All eyes turned, and sure enough, she was right. There, quite a ways away, was Twilight. And behind her, as ever, was her trusty companion, Spike. They were too far to notice the five mares watching them, and within only a few moments, they had walked behind another building, putting them out of view once more. In the silence that followed, Rainbow started to look thoughtful, though it wasn't until she looked back to her friends that her thoughts became known.
"So...anypony gonna talk about the elephant in the room with those two?"
Immediately, Fluttershy's head darted towards where Twilight had been.
"Oh! Twilight has an elephant?!"
Rainbow chuckled to that, patting her fellow pegasus on the shoulder again.
"No, Fluttershy, I'm talking about Spike."
Fluttershy looked back to her.
"Oh, so he's the one with the elephant?"
Rainbow sighed at that, and the other four looked to her with confusion.
"What do you mean, Dashie?" Pinkie asked.
Rainbow rolled her eyes.
"Ugh! Seriously? Do I need to spell it out?"
The blank looked they gave her made it clear that she did, and she slapped her forehead.
"Spike's a friggin' dragon! Was nopony gonna say anything about that?!"
Applejack frowned to her.
"Hey now, Dash! There's no reason ta go an' say things like that! Sure, dragons are usually big, scary and vicious creatures, but Spike's a fine little fella."
Rainbow looked back to her farmer friend.
"Yeah, I know. And don't get me wrong, I like the kid as much as anypony. But...a dragon hanging out with a pony? When has that ever happened before?"
The silence that fell after the question made it clear that she had a point. This was indeed an unprecedented situation they were dealing with, and one that Rarity too was willing to speak on.
"I must confess, I too am curious as to how the two first met. After all, one doesn't simply stumble on a dragon, willy-nilly."
"Oh, Twilight didn't stumble on him," Fluttershy countered.
The animal carer now had the undivided attention of her peers, and while she initially shrunk back at their gaze, she eventually mustered up enough courage to elaborate.
"Um...on the day he and Twilight came here, he told me the story of his life. It seems Twilight was the one who hatched him, back when she was a little filly."
Pinkie gasped loudly, bringing her face a mere millimetre away from Fluttershy's.
"Wow! Really?!"
Fluttershy, taken aback by this, nodded.
"Er, yes?"
Pinkie giggled happily, clapping her hooves together.
"Eeeeeeeee! Do you girls know what this means?!"
They looked to her, shaking their heads, and Pinkie, after stifling what had to be another massive fit of giggles, just came out and said what she was thinking.
"That means Spike's her son!"
Applejack nearly chocked on the bit of milkshake she'd happened to be drinking as soon as she'd heard that, and after beating her own chest to dislodge what was in there, she looked to her party-loving friend with incredulity.
"Beg yer pardon?!"
Pinkie shrugged.
"What? It's obvious! Twilight hatched him, then probably raised him too, so ta-da! She's his sweet Mommy!"
Applejack scratched her head.
"Er, ah ain't no expert or anythin' but is it, ya know, allowed fer ponies ta adopt dragons? An' how old was Twi when that happened?"
Pinkie blinked, thinking on that.
"Huh...yeah, I guess she would have been a bit young to be a Mom back then."
Rainbow chuckled.
"Unless those Canterlot types are way more lenient about this stuff than we thought!"
Rarity let out a "huff" at that.
"Don't be silly, Rainbow! Canterlot ponies are the most prim and proper types you'd ever likely meet! They wouldn't allow such a controversial matter as a child being declared a Mother!"
Rainbow arched an eyebrow to her.
"Oh yeah? Then what is their relationship, Rarity?"
Though slightly taken aback at suddenly becoming the centre of attention, the fashionista quickly recovered, clearing her throat before giving her own thoughts on the matter.
"Well, far be it for me to speculate on such personal things, but I'd suggest the relationship is closer to that of siblings."
Fluttershy seemed interested by that prospect.
"Oh, so he's like her adopted little brother?"
Rarity smiled to her.
"Indeed, darling! The age gap is the obvious clue here, and when you look at them together, they act more like...well, like myself and Sweetie Belle."
She turned to Applejack.
"Or like you and Apple Bloom. The younger sibling helping out with the work of the older, and such other things?"
Applejack, adjusting her hat slightly, chuckled.
"Yeah, can't argue with that. Ah do see a lot o' what me an' Bloom have in those two."
Then, a new thought came to the earth pony mare, and she gave a sly look to Rainbow.
"Say...what did y'all think Spike was ta her, Rainbow?"
Rainbow seemed uncertain all of a sudden.
"What? Me?"
Applejack nodded.
"Eyup. Yer the one who brought this up after all."
Rainbow scratched the back of her head slightly as she thought on that.
"Well...maybe he just works for her?"
Her friends all looked to her as if that was a ridiculous thing to say, prompting an immediate explanation on her part.
"Hey! Don't look at me like that! He's supposed to be her 'assistant', right? That's what he calls himself. So, I dunno, maybe Celestia gave him to her as a little helper or something?"
Rarity seemed aghast at that.
"Rainbow Dash! Are you suggesting that our beloved Princess Celestia would deign to bequeath a living creature as a live-in servant?!"
Rainbow frowned to her.
"Rarity, you and I both know I have no idea what the word 'bequeath' means."
Rarity sighed.
"I'm saying it's not like her to just do something like what you're suggesting. Besides, Twilight very clearly regards him as more than just hired help."
Rainbow leaned back into her chair, folding her forelegs.
"Oh yeah? Well if he's not that, then what is he to her?"
"Ahem."
The second voice caught all of them off-guard, and very slowly, they turned to see that, just as they feared, it was Twilight standing there, looking to them with utter seriousness. Beside her was Spike, who seemed to be just as nervous as they were, if only because their conversation hadn't been something that Twilight would want said behind her back like this. The five mares understandably looked rather embarrassed, not to mention a little ashamed. But, to their relief, Twilight did not become angry at them. Instead, she sighed, putting on a small but genuine smile as she reached over and held Spike closer to her.
"You want to know what he is to me? Simple..."
Slowly, she glanced down to him, her expression growing ever softer.
"...he's my friend."
Spike smiled right back, small tears forming in his eyes, and without even a word, he embraced her in a hug, which was eagerly reciprocated by his carer. The other five smiled to this, and Rainbow, after fighting against the urge to go "dawwww" at that sight, gave a quick chuckle.
"Yeah, okay, I can settle for that."
Author's Note
Just to clarify, this story idea came to me prior to the airing of Sparkle's Seven 
