So, I'm thinking about taking a stab at the "Baby Surprise Jacket." The pattern says to use 3oz of Shetland Wool. I know that many of you have done this pattern. I want to make this a little bigger than a newborn size (baby is to arrive in summer). I think the Shetland Wool will be to fine. If I go up to worsted, how much yarn do you think I will need?