The world has changed a great deal in the five years since the Princess and her friends left. Mostly, Polaris thinks with satisfaction, for the better. She has a lot more work to do now, of course, or a lot more complicated work, anyway. The Royal Friendship Guard (a compromise name, though it only took her a few months to be able to say to business contacts with a straight face, making it one of the better options) is several thousand strong now, and operates throughout the world. There's no guarding of princesses left to do at all, of course, and she hardly runs it all herself, but she thinks the Princess would be proud of the work they're doing in her name: feeding the poor, supporting good causes, advancing peace and international cooperation.
Whatever Lou and David do; she's finally convinced they're doing good, but still doesn't quite understand the shadowy world they do it in. Of course, she supposes, that's why they do it, not her. She's less sure how the Princess would feel about the increasingly religious attitude among some of the younger members. She can't deny it was always there, of course, can't deny it in herself, for that matter, but she feels it's different with those who've never met her, who don't realize she's a pony of flesh and blood, easily embarrassed by the appearance of worship.
Or, she muses, smiling a bit as she thinks it, maybe she's just getting old, and wants those kids to get off her lawn. After all, she still finds the time, every week, to sit for an hour and look at the tree-shrine in the park outside their office. It's actually the same tree that stood outside the Pony back in the day. The City couldn't let it stay there, once it became a site of international pilgrimage, simply because it was disruptive to traffic, so they were glad to let Polaris move it here. It's thrived since then, and now is nearly large enough to carry all the prayers and gifts. Almost. At least its wide branches, draped in purple and blue and silver, still look beautiful in the late-summer sun. Polaris can't help but smile, always, to look at it.
Today, though, as she looks, her quiet thoughts are broken by a twinkle of purple light from the trunk, inexplicable and brief - one might say, a sparkle - but unmistakably there, at least to her. Before she knows it she's on her feet, then running, though she doesn't mind, since now she's laughing and grinning and can't get to the tree fast enough. There, suspended on a thick purple ribbon from the largest branch, is a beautiful purple envelope bearing an achingly familiar six-pointed star, and Polaris's name in an elegant hand.
Careful not to damage the envelope, hands moving with all the precision of her training, which she's painstakingly maintained, she pulls the enclosed letter out. Her discipline remains good enough that her hands shake only a little. There, sitting cross-legged under the shrine-tree, ignoring the growing crowd of tourists that saw the sparkle, or heard about it, she begins to read.
Dear Polaris,
I'm sorry it's taken me so long to write this. So much happened so quickly, when we got back! We filled Celestia in, of course, on everything. She especially loved to hear about you, and said you remind her of some of her favorite captains of the guard, and should be proud of all you did. I know I don't always think to say it, but I agree. I'm still not used to ponies people serving me, so I didn't say thanks as much as I should have.
Anyway, I don't know if or when I'll be able to visit. We have a lot to do here. Your world is just the first of many we plan to visit, and I hope someday you'll be able to meet the ponies and humans and other things from the others - there are so many great and strange and complicated people in the universe. But we all still remember you, and all your friends there, all the time. You were the first new world we visited, even if we didn't remember it, and you taught us so much, we'll never forget. I hope you didn't forget us either, or think we'd forgotten you.
Polaris has to stop reading to laugh, looking around at the purple-flagged office behind her, the countless gifts and prayers and thanks hanging from the tree.
We still haven't really solved the memory issue, we've just been sending letters with ourselves. I guess I didn't even tell you about the memory issue, huh, since I didn't know about it when I was there? Anyway, there is one, and we've been sending ourselves notes to help solve it. But Celestia thinks she can figure it out in a few more decades, and before she does, we don't want to come back to Earth to see you all. After all, writing ourselves notes about some new world and our mission there is one thing, but I don't even know how I'd write myself a note that would make me understand how much I appreciate you all, how much I want to thank you for your help, and to make me enjoy, as much as I should, one more night of your wonderfully strange movies or social media.
I promise, though, I will be back. And before that, I'll write. Watch this tree on this date each month. I think we have enough control over the spell to make sure it will arrive then. I won't always be able to write myself, but we'll at least be sure to send on the envelope. Maybe I'll do pictures.
I've included a few letters from me or the girls to other humans. If you could send them along, I'd appreciate it. If you'd like to write back, we'd all love to hear from you. The envelope should return to us in no less than twenty four and no more than forty eight hours.
I'll fill you in next time on some of the worlds we've been to. It's been a wild ride, but I want to make sure the spell works before I write too much! We all miss you and hope we'll be able to come back soon.
Yours,
Twilight
It's getting harder and harder for Polaris to get around now. She's had to cut down to nearly no staff exercises, and increasingly has to run the Royal Guard from her desk, or lean on a younger aide. It galls her, but she knew it'd happen eventually.
She has measured out her life in purple envelopes, and as a point of pride, she still walks to the tree herself, and will until she can't. She doesn't think this one will be her last, or second-to-last; she expects to have several years of them yet, at least, and medicine keeps getting better, but she's accepted that she can probably see the end from here, and the month between each letter only seems to keep shrinking. It's both a curse and a blessing.
Today, November's letter should arrive. The Princess is many things, and high among them is punctual. It's a pleasantly warm day for so late in the year, and the sun feels wonderful on her wrinkled skin. They long ago changed the spot where the envelope appears, since once the public figured it out crowd control became impossible, but Polaris always felt it should appear outside, under a tree, for tradition's sake, so now it simply manifests in her private garden. She still always sends back a small selection of the papers people hang, because the Princess seems to appreciate it, and because she feels it's only appropriate, but now she can savor the letters in private.
She's looking away, lost in thought, and so misses the sparkle of magic, so her first indication that something's different this time is when an unexpected sound fills the garden.
"Hello, Polaris," comes a voice she's never forgotten. Her throat tightens. She can't turn so quickly anymore, but she does her best. She still has a little of her old speed, and she couldn't hold back on this one, even if she wanted to.
The Princess looks exactly the same, and Polaris feels unspeakably old and pathetic and grateful and blessed. Then the soft fur presses against her side, and she blinks back the tears.
"I missed you," they both say at once.
"I'm sorry I couldn't come sooner," the Princess says. "The memory issue was harder than we thought. We still haven't solved it, not really. It's just, now the worlds have grown so close, it went away on its own. The last few we've been to, we didn't lose anything at all."
"I'm sorry too, Princess," Polaris says, "I got old without you."
"Princess, even now? It's Twilight, Polaris. Please. You never had to earn it, but even if you did, you have."
"I'll try," Polaris manages a wry smile, and pulls herself together. "So what brings you here?"
The Princess - Twilight - blinks. "I came to see you. I promised. And I wanted to, besides. But you're right, I suppose. Us world-traveling ambassadors, I suppose we can't ever do just one thing. Even if it is visit a great friend. Like I said, everything seems to be coming together, all the worlds, back in the same magio-physical framework. It should be possible now to build a craft to ride the magical currents between worlds. I'd like to talk to your scientists about it. I was hoping you'd escort me, one more time."
Polaris can't help but grin. "Of course."
Twilight smiles back, but swallows in a way Polaris thinks looks nervous.
"And then, after that, I was hoping you'd come back with me. I know you'd be leaving a lot behind, but I've missed you so. And...if you stay here, I don't know how much longer you'll have. I know sometimes people are ready to go, but if you're not, if you're willing to come back instead...you know a lot about humans, and logistics, and other things we could use, and we have different magic there. You'll get a lot more time, if you want it."
Polaris is quiet for a bit, but she knows that it's ultimately just for show.
"Did you really think I'd say no?"
Twilight laughs. "I'd certainly hoped you wouldn't. But it can wait. I haven't seen you in ages. Let's catch up. Is the Pony still around?"
"Of course," Polaris says, "though you might not recognize it."
"Well," Twilight says, "it seems I have several kinds of catching up to do, then."
And so they do. For today, anyway, the worlds and stars can wait on two old friends.
The End