Vintage 40s-50s Official Girl Scouts USA Dress Brownies Uniform Brown Girls S

Description

This dress is in amazing condition for it's age.  It doesn't look like it was ever worn.  It comes with BOTH belts (a cloth one and an elastic one) and does not have a size tag.  It measures approx. 15" across the armpits and approx. 30" shoulder to hem.
On the right seam there is a little over an inch that needs to be re-sewn.  Very interestingly, there is a false pocket on the left side...secured by a button.  Were they supposed to wear pants underneath?  Not sure what this pass-through opening is for.