MSD/MDD is a kid sized doll that is sometimes called 1/4 because it's about 40cm tall. They are usually a little bigger than 'true 1/4' dolls, aka slim MSD by a few cm. Here's a pic comparing a classic MDD with a 1/4 Fairyland Minifee, who are both very representative of their doll sizes:
So you can see even without the much bigger head, slim MSD dolls have a bit of a shorter torso. They are also 'slimmer' proportionately, which is where the term came from.
Most dolls will fall neatly into one of the two categories, but the MSD kid-shaped doll came first so it has some of the same weirdness of evolution as 1/3s: People wanted more mature dolls so some companies just put bigger bust options on an otherwise kid shaped doll before true 1/4 adult proportioned dolls were made.
SOMETIMES these two dolls can share clothes especially if you've got dolls with smaller busts in the MSD size. Loose lolita dresses are a good example, or stretchy stuff like sweaters.
Fitted stuff tends not to be as cross compatible. If you have a doll that's in between like a Kid Delf, my 1/4 patterns work better because the patterns are designed for dolls with medium-large busts and there are some cut options for wider torsos.
Now let's get to the new MDD dolls!
Here we have all of the current MDD default bodies as of the time of this article.
There are trends in dolls, and the one that's been going strong recently has been for pear-shaped dolls with significantly bigger hips/lower legs.
We see this first with the lower legs of the Mochi body, as most companies will test the popularity of something by making a slight modification before going all in. The Mochi body was popular, but let's be honest: it looks WEIRD.
So now we have Mochi 2.0 which is fully redesigned! This body also comes with Large as the default bust size while the other two come with small as the default bust size. Each body can have a small/medium/large bust, as you can buy option busts separately.
So is the Mochi 2.0 body 1/4 or 1/3 Kid?
It is definitely not 1/4 in the way that slim MSD dolls are 1/4!
This is a whole other body shape, like what a lot of 1/6 scale fashion doll companies have done to increase body diversity. It's pretty stylized, and whether you have a big/small head or big/small bust the doll is going to look either more kid like or more adult like.
As far as patterns go, the Mochi bodies are more close to the 1/3 Kid pattern size.
This is because the bust/waist/hip all line up vertically with the same distances. That makes it possible to add wide hip variations like I do in my 11.5" fashion doll size where most patterns fit all body types and some need their own pattern. It depends on how fitted a pattern is: some patterns only need a couple of adjustments, some need every pattern piece resized.
The large bust will cause more problems than the mochi lower body. The difference between a Volks Small and a Volks Medium isn't much, but it's like they skip a few cup sizes between medium and beach ball large. When you have a bust that is that much bigger/different shaped, you can't just tailor out a curve for a bust like you do for a bigger hip.
I will make patterns in the MSD/MDD size fit as many cut options as I can, so check the description of the pattern, it will tell you which bust & body variations are included. If you're still not sure, send me a message from the chat box in the corner.
For example, this week's pattern works on all hip/leg options and fits busts from small to large:
(pictured on new body with large bust/hip/leg)