Jane Marple's Blue Dot JSK released in 2006, I'm fairly sure its 100% cotton (the tag is in Japanese though so can't confirm). This dress is a dusty blue and was one of the most versatile dresses I owned - could be worn either casual,  classic style, or dressed up sweet and OTT. It has a lace gauze under layer (which provides a chiffon-y trim) and waist tie, which it can be worn with to dress it up or worn without to be more casual. I've attached two worn photos to give an idea of the different ways this dress can be styled. The dress is in good condition, but does have mild fading in the underarms area and is a bit wrinkled from storage. The worn photo in front of the water heater (lol) with the cardigan with red strawberries is most indicative of the real life colour.

Please see more details of this dress on Lolibrary: https://lolibrary.org/items/jane-marple-dot-jsk

The exact sizing is not listed on Lolibrary I have measured it as below:
Bust: 33 inches
Waist: 28 inches

There is not very much give in the shirring, it will perhaps stretch an extra inch.

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