My Gracie Ruth's hair is 'normal' on her body, but does seem a little thin on top. Her brother has enough gorgeous thick silky hair for 50 Yorkiesl.

Doesn't that always seem to be the way. The boys get all the gorgeous hair and long eyelashes. Yorkies are like people, each is unique and individual, even full blooded brothers and sisters.
Yogi & Gracie Ruth

Notice his top knot is standing upright...G's is flopped over. There just isn't enough hair to even keep the scrunchie upright on her head. Poor baby.