You can also do this pattern in DK wt for a 24 month size, but before you dismiss the idea of a baby sweater knit on size 2 (US) needles, let me reassure you. A baby sweater in sock yarn is not really any more work than a pair of socks. Maybe less. No grafting/kitchenering. (No seams, except for a three needle bind off at shoulders.) And best of all, when you are finished, you don’t have a make a second one. Unless you are working with twins. If that is the case, you are on your own.