Pretty cool. Thanks for sharing.
After extensive playing with the 'figure height' settings, I found they really didn't work as well as I wished they did, especially in the neck. Essentially what it does is a apply a scaling values to various body parts, but doesn't otherwise change their shapes. This gives a very rough approximation of body shape at an age, but only very rough. Not so bad going from "ideal adult' to one smaller ("adolescent?"), but increasingly ridiculous from there.
I ended up buying some figures from Daz3D which were modeled at different ages. This is great for discrete transitions, but unfortunately one cannot easily morph from one to the other -- they are all different models.
If you're interested, the models I used were Victoria 3 (or V3), Stephanie Petite (or S3), Laura (or L3), Maddie (again, 3) and the Millennium Baby 3. There exists a Victoria 4, but it's a different mesh than all of the above, so requires different texture maps and whatnot.