SD13 is the "older sister/brother" of dollfie. She is supposed to look about 13 years old, but you can make your doll any age you want.

SD13 is 60 cm high. The body is larger, more elongated, more slender and more adult looking than regular SD. SD 13 has longer fingers, the girls have high-heel style feet and a larger bust and a waist joint.

SD13's face is slightly more angular and defined.
Megu, Nana, Kira and Sara again all have the same face mold.Instead of all having the same chest shape as standard SD has, SD13 girl come with small medium or large breasts. Here is a photo of the different torso/breast sizes.

SD13's head is 9.5 to 10 inches. (smaller than Cissy's head) SD13 and standard SD have about the same size head.

There is also a new SD13 girl and boy body with more attractive joints (but different posability. so some prefer the old body, some prefer the new). Only 1 new SD13 girl body so far (the one that Madoka and Mimi13 have...) but the SD13 new boy body has gone through a few incarnations. (for instance, both Shirou and Captain Cecile both have the new SD13 boy body, however Cecile has different (and better) knee joints than Shirou.) So it seems that Volks is gradually changing the bodies (perhaps based on feedback by owners.) SD13 new bodies come with Volks pure skin. Also there is the new "long legged pureskin body" that both Isao Nanjou and Tohya have.

For comparison photos of the 1st, 2nd, and then 3rd incarnation of the SD13 boy body, see Grace's photos. The first photo, original old body on the far left, the 2nd body (Shirou) in the middle, and the 3rd new body (Tsukasa) on the far right. Frontal, Back, Sitting Front, Sitting 3/4, Sitting Side, Butt Groove.

Also, see Cassiel's comparison of 1st and 2nd SD13 body (FCS and Shirou)