Simply Soft is acrylic too, so I don’t think it’s the material itself that’s causing the stretching. What gauge are you using? If you’re knitting loosely, it may sag. I knit Anouk from Knitty with Simply Soft, and it didn’t stretch.
I’d use a superwash wool. Wool has a lot of crimp and doesn’t sag the way acrylic does. You might try using some kind of ribbing pattern too. That will make it more elastic.
It’s so nice and soft I forgot it was acryllic :rollseyes:
I wanted to use a synthetic because it seems the dog hairs cling to natural fibers more than say a Red Heart - which is the acryllic I thought I should have used. Worked great for my other dog sweaters.