These are modeled by the darling Hunter she is 7 years old and 48 lbs to give you an idea of how they fit. She is wearing a small. The only advice I have is lil girls tend to not pull them up all the way in the crotch area then run off too play. If the do that hey can tear the middle so you just have to let the lil ladies know that they need to be pulled all the way up like their jeans would fit=)
Theses are available in Small/Medium(4-7yrs old) and Large/X-Large(7-12 years old).