looking at your list, I don’t think that Fluttershy has any canon family that has been introduced. The closest thing to a “sibling” she has canon wise is RD who looks after her. In this your list has to omit Fluttershy as you are proposing a canon pairing of SG and DT in the show.

@Crystal Neighybánya  
I’m singling you out because of your “if you don’t like it just don’t listen” defense. That sort of self-centered, irresponsible horseshit infuriates me.

@Tetrominon  
Also, PonyPon said pretty much the exact same thing I did:
 
@PonyPon  

 
So why are you singling me out?

@Tetrominon  
If it hadn’t been for the fact this pic involved Diamond Tiara, I wouldn’t have said anything.

Best PONY + Best FOAL!

@Crystal Neighybánya  
You could also stop dumping this shit in the comments section of every damned Starlight image you come across and just get the motherfuck over it already, for Christ’s sake, since we’re on the subject of “alternatives”.

@Evowizard25  
You can just ignore my comments, you know.

@Crystal Neighybánya  
No, I’m just tired of it, that’s all.

@Evowizard25  
It took you this long to figure that out?

@Crystal Neighybánya  
Okay, we get it. You don’t like her.

@ice1517  
A bunch of colors made into an animated unicorn who’s a wannabe despot.

@Crystal Neighybánya  
A bunch of colours made into a animated unicorn.

@Evowizard25  
A wannabe despot who happens to be a unicorn.

@Crystal Neighybánya  
A unicorn.

@Vree  
Then what was she?

@Vree  
And that their girls. And their adorable/sexy( In DTs case, when she’s older)

Don’t think they have much in common other than the colors, honest.

@Crystal Neighybánya  
She’s not…

@Evowizard25  
I can see them discussing their past
 
SG: So, what did you do before you turn good?  
DT: I used to pick on the CMC for being blank flanks. What did you do?  
SG: Well, I brainwashed several ponies and formed a cult by removing everyones personality and cutie mark, the made a village with said ponies, then I tried to do the same to Twilight and her friends, then after that failed, I tried to murder her and the other ponies, then I stalked the princes for several months before making a scroll that allowed me to travel through time, and tried to stop the Rainboom from happening, so Twilight and her friends wouldn’t get their marks, which resulted in all hell breaking lose in several different timelines, including one where basically everything got destroyed, before heading back to the present, and almost getting rid of the scroll, which would have resulted in any of those timelines happening. Eh, Diamond?  
DT: UUUHHHHHH 0_0……………  
SG: why does everyone keep doing that?

I think it’d be incredibly interesting and would lead to some great and heartwarming moments.

Maybe it’s just a false positive from the relief over this theory not being yet another “long-lost mother/daughter” pile, but this sounds like a fairly decent idea.

@PonyPon  
The last thing we need is for Di to start looking up to an ex. totalitarian dictator.

Silver Spoon needs a “sister,” too.

I think Diamond already has one of the worst role models imaginable, she doesn’t need another.