This pattern is part of the WOOL - Issue #1 -Vests for Babies and Toddlers Book. Five basic vest styles are given for both DK and Worsted weight yarns. Each of these five basic styles is written in 6 sizes.

The Preemie Vest is a bonus pattern from the WOOL book.
A small change in yarn weight will make the whole difference.
I used the basic round neck DK pattern, with a soft fingering weight wool, but the gauge was much smaller, so the vest ended up tiny. Don’t forget to adjust the length according to the size you are knitting.
The classic rib is changed by tiny cables on the edges.

Credits:
Photography: Kira Kletsky Photography
Styling: Galia Ornan