Blanket Advice Needed


I am fairly new to knitting and am trying to learn as I go. I have a question. I’m trying to knit a baby blanket for a friend, and found a yarn I’d like to use. It is 63 yards of yarn per skein, and is 4st/in using US size 10 needles.

If I wanted to use larger needles, say size 12 or so, what would happen? I’m thinking just a seed stitch or some other simple stitch for the blanket. Would the weave be too open or would something else go wrong?

Also, if I want the blanket to be approximately 36x48 inches, I am having trouble figuring out the number of skeins I will need for the project.

Thanks for any advice!

Going up a size or two on the needles should work out fine, though I’ve never heard of size 12s; sizes are 10, 10.5, 11 and 13 but there’s a big jump in size from the 10.5 to the 11. I’d think you’ll need about 200 yards or so, about 3 or 4 skeins of that yarn.