Well it's basically meaningless now that vanity sizing is a thing.
I meannnn she could be 160 lbs....she has literally 0 muscle tone...I bet she's never seen the inside of a gym...she's not size 6 though.
http://www.fitmodelsla.com/fit-models/size-6/
If you click on "fit models" you can see what a size 2-10 looks like.