As long as you are getting gauge, substitute away! I very rarely use the suggested yarn.
The only thing I would suggest is washing & blocking a gauge swatch first, because the 100% cotton will behave a little differently.
OTN: - Tree of Life afghan, socks, afghan for Dad, Tura Maeve baby dress, alpaca Winter Mountains scarf, Frida poncho
Recently FO- Quinn cabled bag, Evangeline fingerless gloves (2 pairs), Topknot baby hats, pompom & earflap hats, 8 pairs of socks, Baby Folkwear Caftan, Debbie Bliss Baby Shawl (blanket)
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