I think it depends on the PJ. Molly's PJs are really big. A lot of the ones with elastic waists stretch a whole lot. My little cousin in a 3 juniors and she would actually need a Molly Medium pj. I saw the Paisley ones at AGPNY, but I will double check again if I get there tommorrow. The waist was pretty stretchy and the shirt was empire waist so it leaves a lot of room.
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