Author's Note

No clop this time. Setting some things up.

Purity

A strange muffled echoey noise emanated from the hole. Applejack sprung up onto the rocks and said, "Mama? Papa?"

Bright Mac's voice came back, "Jackie? What's going on?"

"You got petrified and buried. We just found you and had a unicorn free you."

Bright Mac, his head still visible, observed, "We weren't under a big pile of rocks to begin with."

"Yeah, that's why we didn't find you right away. Want a hoof up?"

Bright Mac disappeared briefly, and Buttercup poked her head up. "I'll come first." Buttercup clambered out of the chamber, assisted by her children. She got her hind hooves onto the stones, and then cleared the hole.

After blinking away the effects of dark being replaced by facing directly into the setting sun, she got a look at her children. "All right, Biggie, you're obvious. And you're Jackie. Wow, we must have been frozen for a long time. But who are you? One of Fritter's kids?"

Apple Bloom volunteered, "I'm Apple Bloom. Your younger daughter."

Buttercup objected, "I only have two children."

Applejack, meanwhile, finished hauling her father up out of the hole. "Well, as far as we're concerned, you have three. If we're not sure where she came from… She's still mah sister."

Big Mac added, "And mine."

Bright Mac laughed, "All right." He finally got a good look at his son. "Wow! We gave you the right name after all."

"Eeeyup." And with that, Big Macintosh hugged his father warmly.

Buttercup, meanwhile, looked around. "Farm's still in one piece. Is Granny okay?"

Applejack nodded. "Still hanging in there. Grand Pére came back and we got the family all sorted out, but then he passed on a few months back. A shame for you to have missed it."

Buttercup covered her mouth with a hoof. "Really?"

Big Mac nodded. "Eeeyup."

She was thoughtful for a bit; Bright Mac's gaze fell to Sugar Belle, and he broke into a smile. "And this is the unicorn who saved us?"

Sugar Belle stepped forward and bowed lightly. "Actually, I'm not much good with spellwork. I'm Sugar Belle, Big Macintosh's wife."

The smile froze. "Ah. Is that so."

Big Mac vaulted down to her, turned, and put a hoof over her neck. "Eeeyup."

Buttercup seemed to be at a loss for words. She looked past Applejack to her husband, and he back to her. Then he turned back to Sugar Belle. "Do you have any children?"

Buttercup added, "Expecting?"

"Eeenope."

"Not yet."

Bright Mac and Buttercup exhaled. Sugar Belle and Big Macintosh shared an apprehensive glance.

Applejack raised an eyebrow, but didn't comment. "Right, so though the house is pretty full, we aren't overflowing. I can share with Apple Bloom if it comes to it."

There was an awkward silence, which was broken by Twilight Sparkle gliding down. "Apple Bloom! Report, please?" Then, more broadly, "Hello, everypony."

Apple Bloom glanced at her family and carefully worded things, "I took care of Fluttershy, Scootaloo somehow agreed to drag herself through taking care of Rainbow Dash, Sweetie Belle took care of Pinkie. Also, you haven't spoken with…"

Twilight held up a hoof. "Hold on a moment, Apple Bloom. Are you two Bright Mac and Buttercup, nee Pear Butter?"

Her head turn suddenly brought her horn to their attention, and they suddenly realized that she was an alicorn. They bowed as best they could on the awkward footing. Bright Mac said, "Yes, princess… Cadence?"

Twilight smiled. "No, I'm not princess Cadence. I'm princess Twilight Sparkle."

Buttercup gasped. "What happened to princess Cadence, then?"

"Come again?"

Buttercup blinked in doubt. Bright Mac explained, "Your Highness, we thought there could only ever be just one other alicorn besides Celestia at any time, and sometimes none. That's been the pattern for hundreds of years. But if there are two others, that's not bad, just unexpected."

Twilight grinned. "Actually, there are four others besides Celestia."

Quietly, Bright Mac hissed at Applejack, "Bow, fer cryin out loud!"

Applejack laughed. "I don't bow to Twi." She jumped down and hugged her instead. "And you don't need to either. We've known her since before she was a princess, and outside of court she don't want anypony bowing to her either."

"Yeah, I tolerate it in court. Here, stand up already!" Buttercup and Bright Mac straightened. Then, to the three siblings, "So, you went ahead with Starlight Glimmer's plan!"

Buttercup's confusion did not have much room to grow, so she simply asked, "What does Starlight Glimmer have to do with this?"

Twilight suggested, "How about we not drop any more bombshells on you until you've had your Pinkie Party? Where should that be?"

Applejack said, "Barn."

Apple Bloom jumped down off the rock pile and offered, "Castle. Show them the new stuff."

Big Mac said, "If today isn't a good day for her sense, we need to tell her instead of her popping up on her own. If it is, she could be at the barn already. So we can drop by the farmhouse and barn on the way to the castle. It's almost on the way, so no time lost. Plus, Granny Smith is there."

Everypony but the parents looked at him oddly for a moment, but his plan made sense, so they headed back to the farm.

As they walked, Sugar Belle continued to sense a cold shoulder from her parents in law, so she took her concerns head on. "Do you disapprove of me?"

Buttercup laughed nervously, eyeing Twilight. "You, personally? No, not at all."

Bright Mac, though, looked to Twilight directly. "Princess?"

She turned to him. "Yes?"

"I, ah… How much do you know about earth pony magic? Were you an earth pony before you ascended?"

"No, unicorn, and I freely admit that I haven't explored my earth aspect enough. I've just been so busy. But I do have extensive experience with earth pony magic being done by others. Why do you ask?"

"Well…" He took some time to gather his thoughts.

Apple Bloom, having run ahead, ran back. "Starlight's there. We gotta lay down the rules!"

Applejack sighed. "Oh, this nonsense again. All right. Mom, Dad? Starlight Glimmer is the one who saved you. I know, you met her before. Don't tell her anything about the past unless she didn't have anything to do with making it happen. She's a time traveller, and it'll help avoid paradoxes or some gobbledegook like that."

Twilight amended, "Her system avoids any possibility of paradox, but it does become less stable if her actions face an effective paradox avoidance constraint. If it goes unstable, then this becomes a spoiled timeline and never really happened."

Applejack nodded. "Like I said."

"No, this is much better than an actual paradox. A paradox would be able to change the present and possibly wipe out Equestria. This is much smaller. Worst case, it just ends up reverting back to, like, an hour ago and fizzling the loop spell."

Buttercup murmured, "So, what if we didn't really want any of this to happen? Missing my childrens' childhood? Just put it back the way it was yesterday? You say it's not dangerous?"

Twilight pointed out, "Yesterday, we assumed you'd been eaten by timber wolves seventeen years ago. Are you sure you prefer that outcome?"

She blanched. "No. I'll try to avoid breaking the timeline, then."

Twilight nodded. Then, to Bright Mac, she asked, "So, you were saying, about earth magic, as pertains to potential disapproval of Sugar Belle? Is it simply that you've been using primo-stemmaturgy? That is, the magic in maintaining a pure family tree down the first offspring line?"

Buttercup sighed in relief. "Yes. And Big Mac is our first, so it's a bit concerning that Sugar Belle isn't an earth pony."

Big Mac roared, "Hold on an applebucking minute! Are you saying Ah can't marry mah wife? Ye hardly know her! Just one look and it was icicles. And over a bit of tribalist nonsense?"

Pear Butter's ears flattened back. Bright Mac shouted back, "It's not tribalist!"

Applejack rejoined, "You're saying he can't marry a unicorn. Sounds like it."

"No, definitely can. Just the firstborn. Both of you can marry whoever you want! Pegasus, unicorn? Love 'em to death, and any kids you have. They're in the family. And Sugar Belle here is fine too, so long as Big Mac's firstborn is with an earth pony." He suddenly looked aghast. "I mean…"

"You want me to run off and have a kid with some pure earth pony and then we - she has to raise 'em? How is that not tribalist?"

Twilight cut in, "Everything else aside, primo-stemmaturgy isn't tribalist, Big Mac. My family uses it too. Shining Armor and I are exceptional in unicorn magic because of it. And you've met my parents. Do they think pegasi or earth ponies are lesser?"

"I didn't sign up for some breeding program!"

"It's not breeding, it's carrying a flame forward in one descendant. And it's just that if you want to be solely focused on, say, farming or high-power magic, it helps. For most focuses, mixing helps. Just, not farming. And it's not as bad as you think." She took a few moments to recall something, and then a moment of self-doubt because of the implications her vision had had on the reliability of her memories.

Bright Mac took her stop as permission to continue, "I meant to say… we'll love your wife and kids no matter what. Period. End of story. Also, and this is kind of important, there is a big advantage we've had and you have, that if you do the most obvious and natural thing and just start having children, those children will not have."

Big Macintosh stared. "And Applejack?"

"Her kids will probably leave the farm because your kids will be much better at it than they are. And they'll be better at something off in the town than your kids, or something, and that's fine."

Twilight took advantage of the lull in the tension to suggest, "I know of a way that everypony can get what they want, here."

Big Macintosh took a couple deep breaths, glared daggers at his parents before looking back to her, then asked, "What."

Twilight took a deep breath. "Four generations back, one of my ancestors along the primo-stemmaturgical line was an earth pony. To make their firstborn, she donated eggs, and their first children were carried by a unicorn surrogate mother. It was her daughter; she just didn't bear her. It was a risk because the line would have been broken anyway if none of the children had been unicorns, but one was, and it all worked out. They reduced the risk by implanting quintuplets or something like that. One of the unicorn fetuses lined up to suck up the magic, well before the moment of soul blossoming. Then they aborted most of the others, to get it down to a reasonable two. And that's why I have earth ponies as my great great grand mother and a great grand uncle, right along the primo-stemmaturgical line of over a thousand years. One of the few left after all this time."

Buttercup said, "If it was quintuplets, then we'd have a one in thirty-two chance of dropping the line?"

"Not quite that good. The math gets complicated, especially with the false positive and false negative rates on the many tests, and different tradeoffs between accuracy and loss from waiting too long." She furrowed her brow in thought. "Probably one in twenty or so, rough estimate."

Bright Mac swallowed. "Still, one in twenty. I remember all the times I've crit failed."

Buttercup laughed. "Poor Flashburn the barbarian, hopelessly trapped in a spider web due to a succession of ones."

They glanced back to Applejack and Big Macintosh, and their laughter receded. Bright Mac coughed and said, "We'd accept that risk."

Big Macintosh had been watching his parents through this. "You're getting so het up about this. Why is it so important?"

Bright Mac gestured to the farmhouse just ahead, and out across the fields. "It's what this farm is built on. Lose this, and your kids can't keep this place up half as well as you can. Jackie's kids won't carry as much of it either. That's why we haven't grown and grown with more farms - the line goes only to the first born. We and our ancestors built this, not just for you and your children, but their children and their children, and so on. And even with the princess's plan, that's at risk here."

Applejack took a deep breath. "Well. You say half as good. So we have twice as many kids as we would have, and we run our farm like they do in Apploosa. Is there a problem with that? Are Braeburn, Fritter, all those other Apples lesser just 'cause they were kids of second and third kids?"

Bright Mac took a deep breath. "At farming apples? A little. How many does it take to get those fields harvested in Apploosa? Can they do a single buck for a whole tree to go straight into buckets without bruising them?"

Applejack squinted in recollection. "Yeah, Braeburn can do that. Has to set up more carefully 'n I do, and sometimes he takes two bucks, but it's not like he's half the farmer I am."

Apple Bloom pointed out, "Actually, sis… I think I really would rather have just you on the farm than two of Braeburn. Right, Big Mac?"

Big Mac reluctantly nodded.

Bright Mac sighed. "I'm not saying we can't be Apples without this. I'm just saying… just… it was a surprise."

Big Mac shared a look with Applejack, and dubiously said, "I'm glad to hear that was all."

Twilight loudly said, "Oh snap! I just remembered, that spell has to be cast by the surrogate herself!" Applejack sat down and threw her hooves up in the air, willing it to stop. Apple Bloom giggled nervously.

"Meaning unicorn. And that's just what we're trying to avoid." Twilight raised a hoof. "But! I'm part earth pony now. That's enough not to trash the whole line."

Buttercup exclaimed, "You would?" Twilight nodded, and Buttercup continued, "Wow, you must be closer to the family than I thought!"

They came to the porch, where Starlight and Granny Smith were sitting on rocking chairs sipping iced tea. Granny called out, "Good to see you back!"

Bright Mac swallowed harder upon seeing her. She wasn't looking as well as he remembered, and he'd forgotten to adjust his expectations. He carefully approached her, unsure of how firm she was - she had stayed here instead of coming to the rock pile, after all. She got up and hugged him, then Buttercup. "Nice to have you two back. Now don't cause too much trouble, you hear?"

Bright Mac looked to Buttercup, then back to his mother. "Seems as if we already did. We were a bit thrown off by Sugar Belle."

"Wonderful mare, glad to have her in the family. And you should be too. Can't wait for their first."

"So… uh, no problem that she isn't an earth pony?"

"Nope. None at all. Everything's already taken care of."

The desperation in Bright Mac's voice stabbed Big Mac. "How? You didn't even hear our plans!"

"Don' worry bout it none. All goin' be fine, end of story." Then she got a slightly furtive look, which she cast across her grandchildren. "Probably. Depending. Nah, it's good. I was watching out for the farm too, you hear? All. go. ing. to. be. fine. No need to hash it out now. I don't want another word spilled over it for at least a week. Now, if I know Pinkie, there's going to be a party in the castle. Let's head out and not keep her waiting to figure out what she's throwing it for."

There was indeed a party at the castle, a little one just with the elements the Crusaders and Spike and the Cakes as guests. Pinkie was sad that it was getting a bit late for the full-scale event this deserved, but promised a big one the next afternoon. Applejack showed off her throne to her parents, who began to understand why Twilight would volunteer to bear their grandchildren, and everything went swimmingly for everypony but Big Mac and Sugar Belle.

Starlight barely attended, but instead retreated to her room to avoid any possible spoiler resonances. Partway through, she dropped by and came to Sugar Belle. She whispered, "I have train tickets to Our Town. The eleven o'clock. Want to go get your father? Assuming I will have succeeded?"

She jumped up. "Yes, please!"

To Big Mac, Starlight added, "And I imagine you'll want to come, too. I can get a third ticket."

Big Mac tensely looked over to his parents, then nodded. He resolutely approached them. "Hey."

Buttercup looked up, concerned. "Yes, Biggie?"

He cleared his throat. "Sugar Belle also has her dad missing, and Starlight wants to rescue him too. So we'll be heading out. Be back tomorrow evening or so."

"You're going tonight? But of course you are. A chance to have your father back shouldn't wait. Definitely, save him first, we can meet again later. Not like we're going anywhere."

Bright Mac nodded, then gave his son a hug. "Son… I'm sorry about this mess. If Granny Smith says it's going to work out, I guess I was just silly."

Big Mac shook his head. "Not silly. The farm is a big deal. Just…"

Bright Mac nodded. "I know. I've been imagining Buttercup was a pegasus. It'd be hard. Take care, see you tomorrow."