Since I’m a tight knitter and using a thicker yarn, I went up a needle size. I also decided to use snaps instead of buttons and bought these to hand sew on with the back stitch.

When splitting the front and back, the last row I knit was 54, doing the split on the next repeat starting at Row 39.

For the sleeves, I decided to split the stitches over 3 needles. I started my round right after the arm hole, put 7 stitches on that first needle, 10 on the next two, knit the final 7, then picked up 4 (the next row starting in the middle of that needle). I did the first decrease on the 5th row (not including the first round of picking up stitches). I also switched the decreases to K2Tog, K2, SSK. After that, I did a decrease row every 15th row. I knit 5 more rows after that (to get to 15cm for slightly longer sleeves), then switched to smaller needles and finished after ribbing.

Blocked Measurements:
Back Length: 41cm
Front Length: 35cm
Total Width: 46cm
Sleeve Length (from collar to end of sleeve): 27cm

I had yarn leftover, so I improvised a hat to go along with this onesie.

This ended up fitting our son when he was 6-10 weeks old.