"Kululu."
The frog in question looked up from his glass of milk. "Yes, Twily?"
"Uh...I was wondering...about...children..."
Kululu started choking, and gasped "Ah-WHUH?!?!" Twilight shrieked "I'm sorry! It's my fault! Eheh..." He nodded. "You want a...foal? Or keronian...? I'm confused." She shrugged. "Well, I don't know how it works...we weren't even supposed to meet each other, remember? N-not that i regret doing so! Cause you're the greatest thing ever, and...uh..." Kululu chuckled. "Alright, I get it, silly filly." Twilight fiddled with hwer hooves. "I can only think of one way to reproduce at the moment..."
~2 hours later~
"Hi Rainbow Dash! How's Giroro?"
"Uh, good. Why is your face red, Twi?"
"Um...heh...me and Kululu are trying to..."
"Is that possible? I think you should ask the Princess about that. Later." And she took off. "...Spike...take a letter..."
Dear Princess Celestia, is it possible for a Keronian and a pony to reproduce? Me and Kululu are trying the best we can. Sincerely, Twilight Sparkle
"Wait...you mean you're-" Twilight shoved a hoof in his mouth. "You'll understand when you're older Spike..."
"Uh, Twilight, I think the Princess has-" Green flames shot out of his mouth. "...replied..."
My faithful student Twilight Sparkle, the spell contained on the last page of this book is Star Swirl the Bearded's secret unfinished masterpiece. He was never able to get it right, and thus abandoned it. I believe you are the only pony who can understand and rewrite it. As for your question, it has come to my attention it is possible to reproduce with said husband of yours, but it is no guarantee. Take this into consideration before you try anything...shall I say, rash.
Princess Celestia"
"This is great! We might be able to after all! But let me look at this spell. From one to another, another to one. A mark of one's destiny singled out alone, fulfilled. That doesn't make any sense. It doesn't even rhyme!" She threw down the book in defeat. "Well, I can investigate tomorrow. Let's get some sleep..."
"...Life in Equestria shimmers
Life in Equestria shines
And I know for absolute certain
That everything
Yes, everything
Yes, everything is certainly fine
It’s fine
Yes! Everything’s going to be just fine!"
"What did we miss?" All the frogs ran up to the castle. Kululu ran over to Twilight. "Hey, now we can- what the- GAHTWILIGHTYOUHAVEWINGSDOESTHATMEANYOUREAPRINCESSWHATTHEHECKISGOINGONAMIROYALTYNOWIAMSOCONFUSEDDOIBOWTOYOUNOWORWHATABOUTCELESTIANDLUNAWHOLLRAISETHESUNANDMOONANDPREFORMDUTIESWHATONEARTHISGOINGONMYMINDCANNOTPROCCESSTHIS!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!" He paused to breathe in.
"Whoah dude, calm your blood pressure.Where have you been? It's still Twilight!" Rainbow retorted. Celastia gasped.
"How could I forget?! Fillies and gentlecolts, your new Prince Kululu! Go on, say something!" He shook with fear.
"Uh-um...I met Princess Twilight in a mishap with my machine, and I-I always thought she was beautiful, but now she is even more so. Sh-she's the light of my life, the the peanut butter to my jelly, the twinkle to my star, the seeds to my orange, the music to my song, the stars to my nebula, the cheese to my macaroni, the brightness to my sun, the cup to my cake, the lock to my key, and the friend to my friendship. Friendship...is not something you learn in school. But if you haven't learned the meaning of friendship, you really haven't learned anything. Rare as is true love, true friendship is rarer. Let us be grateful to people who make us happy, they are the charming gardeners who make our souls blossom. I don't need a friend who changes when I change and who nods when I nod; my shadow does that much better.The friend in my adversity I shall always cherish most. I can better trust those who helped to relieve the gloom of my dark hours than those who are so ready to enjoy with me the sunshine of my prosperity. I cannot even imagine where I would be today were it not for that handful of friends who have given me a heart full of joy. Let's face it, friends make life a lot more fun. SO HOLD ONTO THAT FRIENDSHIP, EQUESTRIA! IT COULD CHANGE YOUR LIFE!!!!!" Everypony cheered.
"Hey Giroro, are you crying?"
"Wha-no! it's-it's liquid pride. Completely different thing."
"Surrreee."
Everypony was celebrating with their family, friends, and loved ones.
Except for one filly.