This pattern called for bulky yarn on size 9 and 10 needles. I made it in worsted so reduced the needles 2 sizes. To get a size 12-18 mos., I followed the directions for size 2-3 years except for lengths, which I kept at the number of inches for 12-18 months. Worked out perfectly, body turned out 11”w x12”long. Warning: I found a few errors in the cable directions so be careful. I changed the cables to X’s and O’s just because they seemed more girly. I made the collar lie flat by starting with 2 rows of #7 needles. Next row I switched to #8s and stuck an extra purl in every other one across the back of the neck (right side facing you). Final two rows and BO I did in #9. Seems to behave itself now. The sweater turned out nice and soft, even though there’s loads of texture.