I wasn't as precise with my gauge calculations as I usually am. One needle I tried was too big, the next I tried was too small so I chose the needle size in between and never checked the gauge again. I figured a baby set will fit when it fits, a wee bit "too small" or "too big" won't matter.
I tried just now to check the gauge for Kathy, but there is very little on that set that is in plain stockinette. Across the plain bit at the tip of the leaves I seem to be getting about 9 sts to the inch, which is a little smaller than the recommended gauge. The final sweater is 17 1/2 inches at the underarm instead of the stated 18 inches in the pattern. I intend this outfit to be used to bring a newborn home from the hospital. There is plenty of room in a typical 18 inch "3 month size" for even a large newborn so I am not concerned.
I never did the bonnet as directed. I eliminated the ribbon ties by altering the original pattern to be a hat knit circularly with the next size larger needle (the size used for the lace portion of the sweater). It was a bit fiddly to figure out, and I didn't write down what I did, so can't offer you the pattern. I should get it written down while it is still reasonably fresh in my mind. I'll give you what I remember though....
I started with a central "pinhole" cast on (done with a crochet hook....like circular shawls are sometimes started) and followed the bonnet pattern but omitted the edge stitches (eliminate 3 stitches from all the stitch counts and work only the directions between the *s) and knitting in the round. Of course this means that the "wrong side" rows have to be adjusted to be knit from the right side. Just knit where it says purl and purl where it says knit, but also remember that the order has to be reversed. Be sure that you get that solitary purl stitch in each repeat in the right place on every even row.
One thing that was rather confusing was the fact that with each subsequent row the starting point of the round moved one stitch to the left (because of the yarn overs). That meant that when I got to the garter stitch triangle that separates the leaves, it was half on one round and half on the next....the round change came in the middle of the garter stitch triangle. I had to watch carefully to be sure that I changed from the even row purls to the odd row knits at the right spot. Surprisingly this bisected garter stitch section really doesn't look bad. It gives a slight seam effect that looks fine.
After the leaf section was complete I continued the garter stitch portion until the hat was 4 1/2 inches from the crown. At that point I did 10 rows of stockinette, allowing the natural curl of the fabric to form a roll brim which I later stitched down neatly on the right side.
I used "Bernat Baby" 100% "gentle soft" acrylic, which is a washable/dryable fingering weight that is inexpensive and readily available in my area. The impractical side of me would love to do it in an ultra soft alpaca, but I know that new moms don't have time for fussy "hand wash only" baby clothes, so acrylic it is.