@Background Pony #CA25  

@Background Pony #CA25
 
Sorry for switching between 15 and 16 years.  
I’m tired.  
Scootaloo is slightly over 15 wich means that the Galloping Gala event in question would have occurred roughly 15 and a half years ago.

@Vexd
 
“Though by the sound of things, Celestia probably isn’t going to remember unless they randomly start throwing words around and just happen to hit the key one.”
 
It’s almost bed time for me and I’ll still add the latter part where Celestia has her momory restord in fractions thanks to Luna and How Scootaly found out the truth in fractions too eventually driving a wedge between them.
 
It started out when Twilight later on wracked with the thoughts of witnessing Celestia Pregnant 15 years ago brought up to Celestia the possibility that Scootaloo might be her daughter. Her Biological Daughter.
 
This conversation was done in private.
 
Of course Celestia Scoffed at the Idea.  
I mean 11 months carrying a foal and then forgetting about it.  
Then Twilight asked her detailed questions about the Galloping gala event held 16 years ago. Celestia usually having pretty good memories was dumbfounded that she couldn’t remember much of the Gala that night.  
She has good memories the Gala the year before and the year after.  
In fact that particular year was a blur to her.  
She remembered some things but it is as if certain part of her memory and certain details were lost.
 
Twilight Continued:  
You had a diplomatic visit in Patonie a month after the Gala that year.  
I did some investigation…. you weren’t there.
 
Celestia didn’t even recall going to a diplomatic visit.  
And nopony even bothered to bring it up probably due to fear.
 
Celestia noticed something very disturbing.  
The year she had this strange lapse in memory is a about the same time Scootaloo would have been born.
 
She still wants to find out if there is a connection between her and Scootaloo but she simply dreaded the Idea that Scootaloo is her biological daughter.  
Not that she doesn’t like Scootaloo. It’s that this would render her a complete failure as a mother.
 
Later that night Celestia summoned Luna and ask her help to delve deep in her thoughts.  
Specifically 16 years ago.
 
The princess of the night entered the mind of her sibling when her sister was asleep in her astral form.  
Floating through memories of her sister which is numerous she found a mysterious space with closed doors.  
The doors were locked with magic and behind those doors as Luna has guessed are Celestia’s lost memories.  
Those memories were never erased. Celestia couldn’t recover them.  
When Luna attempted to magically open one locked door with her horn she got shocked.  
The doors were locked with incredibly powerful magic.  
What makes it even more bizarre she recognizes the mana signature.  
It’s Celestia’s magic.  
She locked up her own memory of that year…
 
Luna was dumbfounded and reported what she experienced to Celestia when she woke up.  
Celestia asked Luna to repeat the session again this time she will Join Luna in her dream.
 
To b con’t

@Background Pony #CA25  
Excellent write-up you’ve got there  
 
Though by the sound of things, Celestia probably isn’t going to remember unless they randomly start throwing words around and just happen to hit the key one.

@Vexd
 
 
For the context of this problem see link:  
The answer was too long to post here.
 
http://leovictor.deviantart.com/journal/Princess-Leana-4-RECORD-KEEPING-PURPOSE-461147814#comments

@Background Pony #3B60
 
Weather altering abilities, more than all pegasi ponies in Equestria combined. Ability inherited by her pegasus father Tempest and supercharged by her alicorn mother.  
She can summon rainstorms, hurricanes and her fav lightning. Lots of it.  
She can by using a massive lightning storm direct lightning strikes on simultaneous targets at once or converge then onto her horn and shoot it in one massive lightning blast.  
She has other abilities like creating fog, turn rain into deadly icicles, massive wind blasts. Control over temp etc etc.  
Scootaloo is not a mare you wanna mess with as an adult  
Before Scoot got her cutie mark and cried (which she rarely did) it always rains.
 
Her biggest weakness is to put her in a confined space deep underground where she has less air and moisture to work with.

@soundtea  
That’s where the twist comes in. Even though Twilight has figured it out, Celestia has had all her memories of ever having a daughter wiped. She’s completely unaware at this point

@Background Pony #B1AE  
Pretty much with what Vexd said. The horn comes right as she gets her cutie mark. And her parentage is kinda out of the bag given that her mark uses Celestia’s cutie mark as the sun.

@Background Pony #B1AE  
More or less.  
According to the artist, Celestia had managed to hide a pregnancy with her magic save for one night when Twilight spotted her with her guard down, and in turn lied stating it was from eating too much cake.

If I read this right, then:
 
Adult Scootaloo suddenly grows a horn.
 
Twilight notices Scootaloo’s cutie mark is very similar to Celestia’s.
 
Twilight remembers Celestia looking pregnant.

cloud… lol