@Daneasaur  
I see your point about Maud having a lot less in the way of blank-filling support, I just don’t think that lesser support really warrants quite so much arglebargle about it; I guess I’m just willing to grant the show more benefit of the doubt when it comes to expanding the main characters’ backstories by introducing secondary characters.

@Background Pony #40FB  
The problem is that said photo is supposed to be when she got her mark, yet the actual episode doesn’t have her in it. This makes it a retcon and a sloppy one at that.
 
When SA and Cadance were shoehorned in, the “proof of the past” used were segments where we hadn’t already seen Twilight, such as her first using magic, and even leaving canterlot.
 
Now, we all can make headcanon as to why Maud isn’t around during that party, and personally, I had forgotten that photo and said “Oh, well she’s probably the oldest sibling and already had her mark and was living somewhere else”. But then the photo is there claiming she was THERE when Pinkie got her mark, when she wasn’t.
 
The problem, again, is that while SA and Cadance were shoehorned in, their placement made sense in a stupid way.
 
Maud DOESN’T make sense and requires a significant segment of Pinkie Pie’s backstory to be changed.

@Daneasaur  
So you give SA and Cadance a pass because they were shown in flashbacks when they were introduced, but Maud is “shoehorned” because she was shown in a photo before the episode that introduced her, but not given a flashback montage? Is that it in a nutshell?

@TexasUberAlles  
What I’m basically saying is that, while I like Maud, and I love Canterlot Wedding, SA and Cadance get backflash images showing some empty holes of the past being filled in with those characters, including Shining waving Twilight off THE DAY SHE LEFT CANTERLOT, Maud DOESN’T. Even on her debut appearance, she’s just suddenly “there”. No backflashes, nothing, yet apparently Maud is her “closest sister of all time”… Yet she missed out on the party that gave Pinkie her cutie mark? And we have not been given a reason as to why she wasn’t there?
 
At least while SA and Cadance got a LITTLE backstory prior to meeting them, Maud does not. She materializes and, to this day, doesn’t have an explanation of her existing or even why she wasn’t at Pinkie’s Party.
 
This, sadly, makes me see her as being more shoehorned into the show than SA or Cadance.
 
And again, I don’t dislike her, I think she’s a fun character.

@Background Pony #40FB  
If I could change anything about the first couple of seasons, “mentioning Shining Armor and Cadance before they appeared in the S2 Finale” would be pretty close to the top of the list; making it such a surprise development still comes across as a serious unforced error to me even though I love the stuffin’ out of A Canterlot Wedding as an episode and the Royal Couple as characters. (Almost) everyone seems to love it when they bring back a concept that was only mentioned in passing in earlier episodes, and that would have been a great payoff for something that would have generated a lot of hype from fandom speculation in the interim.

@TexasUberAlles  
 
Making such a major addition down the line is always risky; for Maud, I think it paid off handsomely (and I just like her, rather than love her), for Shining Armor and Cadance, ehhh…

@Daneasaur  
Sure, realistically, Maud was a story element that was added after the fact for whatever reason, but “new information” =/= “retcon”; it’s logically more likely that Pinkie– coming from a large family– would neglect to mention one of her multiple sisters in particular than it was that Twilight would neglect to mention her (highly influential!) only brother onscreen, even though Shiny Armoire had been a part of the planning for season 2 for so long that Lauren Herself was still involved with the show at that point. The problem with slapping a LEFT FIELD!!! tag on new story concepts is that from a storytelling standpoint, where do you draw the line for “really never existed”? Was Pinkie’s entire immediate family itself a “retcon” just because we hadn’t heard a word about them before Cutie Mark Chronicles? It was certainly an unexpected development that she would have grown up in a humorless Horse Amish household. Are any of the ten horsejillion new Apple Family members who show up every few episodes “retconned” just because we hadn’t seen them before (and will likely never see them again)? It was established early on that The Apples are a large family… just like it was established in CM Chronicles that Pinkie comes from a large family. Scale is the only real difference.
 
If they introduced a new Pie sister now, that would obviously be different, but Maud was an update, not a retcon.

@Background Pony #E17E
 
@TexasUberAlles  
OR!
 
Maud really never existed and hasbro retconned her into existence since her other two sisters showed too much emotion to have a “droll and boring” sister for Pinkie Pie

@Background Pony #E17E  
Seriously, that’s one of a bajillion perfectly rational explanations that require no hoop-jumping or headcannoneering whatsoever; some fans just have a baffling tendency to assume that anything that didn’t happen onscreen didn’t happen in-universe at all, which would make it kind of a terrifying world to live in since that would mean Pinkie is the only one who’s ever been allowed to use an outhouse and Bon Bon is the only Pony who has a toilet.

@Daneasaur  
I never understood why this is so hard to explain away: Maud was doing the dishes as her morning chores while Limestone, Cloudy, Igneous, and Marble went out to the farm. They find the party, Maud finishes doing the dishes or notices her family hasn’t come out in a while or Pinkie goes to get her. Bam, Maud explained not being there for the reveal of the party.

@Softy  
It was a tweet of a writer I think

@D_Tavs.exe  
I’ve heard this before, but what is the source for Limestone being older than Maud?

@Ereiam  
I point back to the actual episode detailing her getting her mark; only her parents and marble + Limestone were there.
 
As I said, Maud didn’t exist until Hasbro decided that she needed another sister for “reasons” and then retroactively slapped her in a picture of what looks to be Pinkie’s first party (how there was a camera shot of that in the first place with THAT family, we may never know).

@Daneasaur  
But Maud was around when Pinkie had her first party (or one of her first ones in any case):  

 
I also noticed just now that Pinkie was the first of the Pie daughters to get her cutie mark, despite being the (second) youngest.

@D_Tavs.exe  
The reason everyone has been saying that Maud is the oldest is that it would mean she possibly had moved away from her parents and thus it was the reason she could have been missing when Pinkie had her first party.
 
If limestone is supposed to be the oldest, this just makes things confusing and gives no reasoning as to why Maud isn’t around during Pinkie’s Party. other than the sour taste of Maud being shoehorned in for merchandising

@TexasUberAlles  
Personality isn’t really an argument: Pinkamena’s wasn’t really different from the rest of her family up until she witnessed the Sonic Rainboom.  
Also the Cakes are another example of twins who are completely different in appearance (and aren’t even of the same gender or race): while Pumpkin takes after her father color-wise, Pound’s colors are completely different from his parents’.
 
But I admit that there’s nothing telling us that Pinkie wasn’t found on the Pie’s doorstep while Cloudy Quartz was giving birth to Marble either.

@Ereiam  
If you saw a Human family where the parents and three of their daughters all had roughly the same skin color, features, and hair type– with similarly dour personalities– while the fourth daughter had completely different skin color and hair and personality, what would you think had happened there? Most people would automatically assume she was either adopted, fostered, or was a step sister. In elementary school I knew a brother/sister pair who had the same birthday and were only born like an hour or so apart, but were only related because their parents were both on their second marriage.
 
…Probably in the show they’re meant to be twins because everything about Pinkie is one big running joke including her family, but it’s not a certainty unless/until they actually lampshade it in onscreen.

@Ereiam  
@TexasUberAlles
 
Fraternal twins.

@TexasUberAlles  
Unless pony gestation only lasts a few minutes from conception to delivery (which doesn’t seem to be the case, if “The One Where Pinkie Knows” is any evidence) or they somehow have different mothers who somehow gave birth at the same time (unlikely but not impossible, I grant it), it seems to be a logical corollary to me.

Still doesn’t mean they’re twins, though.

@Ereiam  
Yeah everybody thought that Maud was the oldest since she seemed a little bit taller than the others on Pinkie Pride episode

@D_Tavs.exe  
Oh right, I just checked my facts and Limestone is the eldest (and not Maud, as I thought for some reason). And there goes another headcanon.

@Princess♠Molestia  
For a second I felt so much better that someone else had the same first thought I did, but then I realized who said it, and now I feel horrible again. || Not really. I’ll hold her down Molestia, you get the rope.||

@Ereiam  
I would need to be quadruplets, since Limestone is older than Maud

Man, those eyebrows are hardcore.