Have you seen the Willow Square below? You probably have, and I will provide a link for that additional free pattern below. This is the Patons Willowdale Crochet Cardigan.
This pattern, developed by Katherine Poole-Fournier, elegantly mixes the trending granny square look into a wearable garment. Its lacy back and sleeves complement the relaxed look and feel of this garment.
This is sized in adults from extra small to 5 extra large. The sizes of the squares are different depending on the size you are making. Of course, the larger the sweater, the larger the square needs to be.
There is a construction schematic for the panels as well as a crochet diagram for the square. Note that the square will have more single crochet rounds than the original willow wrap shown below for the different sizes.
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