Pushing open the door with her horn, Starlight trotted into Twilight's kitchen. She found the Princess in an apron, carefully putting a tray of cookies into the oven. When the Princess noticed Starlight's entrance, Twilight hastened her act, dropping the tray and shutting the door to the oven as quickly as possible.
"Starlight! You're here!" Noticing that she was wearing her apron, Twilight's horn ignited and teleported the article out of the room, her face reddening. "Um. Were you here to grab a snack before you go?"
"Nope," said Starlight, a light grin on her face. "I'm not going anywhere."
Twilight shook her head. "But... But I thought you were going to go help Trixie with her magic today. You wouldn't want to let her down."
"Oh, don't worry. I never told her I was going to do that. I only told you."
At that moment, a saffron colored stallion, sporting a goatee and a vibrant sunbeam cutie mark, walked confidently into the room. "How're the sweeties comin' along Sw--eya! St--Starlight! What are you doing here?"
Starlight raised an eyebrow. "First, I live here. Second, where's your robe?"
His horn igniting, Sunburst's robe materialized on him in a flash of magic. However, it was on backwards, its back hanging out in front of him, bunched up over part of his face, and draped onto the floor. Looking down and seeing the mistake, he quickly spun the robe around. By the time his face was fully visible again, his cheeks were beet red. "Well, you see, it's a funny story, that. But, eh, I shouldn't get into that now. You, uh, you're probably wondering what I'm doing here at all. And for that, well, for that I have an explanation!"
Looking up at the ceiling toward the left side of his vision, Sunburst said, "I came here to deliver a message to Princess Twilight about her niece." Sunburst nodded to himself, then cleared his throat and said, mechanically, "Princess Cadence felt it was important that I come here to deliver this message, about your niece, Flurry Heart, to you, Princess Twilight, in person, so that we can properly address this matter."
"Oh my," said Twilight, overemphasizing every word. "An important message about Flurry Heart. How unexpected! What was it you needed to tell me, Crystaller Sunburst?"
"Princess Twilight. Your niece, Flurry Heart, has outgrown her first high chair. So, I am afraid you will need to get her a new one. But fear not! I know the right size, so we can go to the store and sort this out."
"Wow! She is growing up so fast! I am shocked! We must go to the store post-haste so that I am ready if she wants to come visit."
"Yes. Indeed." Turning quite deliberately and forcing a smile onto his face, Sunburst said, "Starlight. Would you like to join us on this trip?"
Rolling her eyes, Starlight said, "First, nice try, but that was the worst performance in history. You two make Princess Celestia look like the best thespian in Equestria." The pair's blushes intensified. "Second, that's why I had to ambush you two. We need to talk so we can drop all of the pretexts here, alright? I'm not oblivious. I know what this is about."
Twilight and Sunburst both sighed and looked at each other. With a nod from Twilight, Sunburst looked back at Starlight and said, "Look, I'm sorry this is how you found out. I really wanted this to go differently. I was going to spend the whole day with you -- Fly kites, play board games, everything you like! -- before bringing you back here to find out. Because I wanted you to understand that no matter who else we have in our lives, we're still friends. And we can still spend time together, just the two of us, even if we get close with other ponies."
"Of course!" Starlight smiled. "That's really sweet of you. I'd love to do that. And, if you still want to, I can even act surprised when we get back here."
Twilight raised an eyebrow. "Uh, don't you think that would be a little weird?"
"Pfft." Starlight flicked a hoof. "Come on, everypony else doesn't have to know that I know. And while I admit the talent does come from leading a prior life of deception and lies, I am a pretty good actress. I think I can convince everypony that I didn't find out."
"Starlight, what are y--?" Sunburst began.
"Who," Twilight interjected, "do you think is 'everypony?'"
Tapping her chin with her hoof, Starlight said, "Huh, I guess I hadn't thought about who you would invite. I'd assume the girls. And then also Trixie and Maud. You probably invited everypony from my old village. Maybe Thorax and Discord, if they can make it?" Starlight stopped and looked between the pair. "Why? Is somepony special coming who is really good at telling when a pony isn't surprised?"
"For your birthday!" shouted Sunburst. At that, Starlight raised an eyebrow and Twilight facehoofed. "Uh... No, no!" said Sunburst. "We just, uh, want to... want to make sure you don't know all the surprises! 'Cause the guest list is part of the surprise!"
"Oh," said Starlight, nodding. "Well, yeah, that's true. I guess I can be surprised by who is there. So, sure, don't tell me." She then looked at Sunburst directly. "And, if it makes you feel a bit better, Sunburst, I couldn't tell what kind of cookies you were making, either."
Sunburst frowned. "That I was making?"
"I mean, that is why you left your cloak in the other room, right?" asked Starlight. "So you wouldn't get it dirty in the kitchen preparing for our outing tomorrow?"
"That makes sense!" said Sunburst, a huge grin forming on his face. "I-- I mean, of course! That's why I left the cloak out there." The stallion's eyes darted to Twilight for a moment. The alicorn was smiling and nodding along.
"Alright," said Starlight. "Well, I'm glad we could clear that all up. It was getting so silly; the lengths you two went through to hide all your planning from me were just ridiculous!" Starlight started laughing. "I can't believe you had Sunburst borrow Fluttershy's tree disguise!" Twilight and Sunburst feigned laughter of their own.
"But honestly," said Starlight, walking toward the pair. She put out both of her forehooves, pulling the three into a group hug. "Thank you so much for putting in all this work." Stepping back a bit, Starlight smiled broadly. "And I promise: I'll act really surprised!" Starlight gave the pair a wink.
"Yes," said Twilight. "Glad we cleared that up." For a few moments, the three ponies stood in silence, two smiling rather awkwardly. Then, Twilight said, "So, uh, Sunburst and I should probably get back to work."
"Oh, of course! I'll let you two go. See you tomorrow, Sunburst!" At that, the unicorn walked out of the room.
The moment she was out of sight, Twilight and Sunburst collapsed onto the floor and let out a pair of emphatic sighs.
"Okay, that could have gone better," Sunburst said. "All that time practicing our cover story feels pretty stupid now."
"Look on the bright side," said Twilight. "Our distraction didn't not work and, bonus, we were reminded about Starlight's birthday in time to do something about it. She even gave us a guest list."
"Yeah, true. I guess that's all good." Sunburst nodded. "But, uh, when do we tell her we're dating?"
"That," said Twilight. "Is a problem for Future Twilight and Future Sunburst. We are Present Twilight and Sunburst, so for now, we plan her a non-surprising surprise party. I'll go get Pinkie Pie as soon as these cookies finish baking."
"Alright," said Sunburst. "While you do that, Starlight reminded me. I need to go give Fluttershy her costume back."
Author's Note
And they all had the best Surprise-Party-Even-Though-She's-Not-Surprised-And-This-Is-All-Just-A-Cover-For-TwiBurst-Ohmigosh-Isn't-That-Adorable-We-Have-To-Have-Another-Party-Just-For-That-But-Not-Until-They-Tell-Starlight-But-Ohmigosh-I'm-So-Excited Party ever.
THE END
And I'd like to give a shout-out to Summer Dancer, whose not-so-recent fic inspired me to give this story another go.
