IRO Noun Floral Smock Top Size S/M

IRO Noun Floral Smock Top Size Medium NWT Beautiful viscose top with floral print. 3/4 sleeves. Size says 38 which would be a US 6. It measures approximately 18 inches pit to pit and 23 inches long. It's a little tight in the shoulders and the sleeves so I'd say even a small could fit this.