Oh, look. Unoriginal dimensions.
I tried to design a character to look young - about ten to fourteen years old.

Something I noticed while out and about - a surprise, for sure! - is that younger girls prefer longer hair. Of course, this is a small sample size.
I hypothesised that older girls have shorter hair because human hair grows at a constant rate throughout their life. Therefore, this character has longer hair to appear younger than my usual style. My previous skins also fit under this rule as my childhood self liked to design them of roughly his age.
Also, the eyes.

Version with higher eyes (and mouth) :