The body and collar is worked in flat and bottom up separately, and then join them together.
Video for how to join rib stitch to vest has been uploaded to instagram: jjloveknitting

size: 2-3 (3-4) 4-5 (5-6) 6-7 (7-8) 8-9 (9-10)y.
needles: 3.25mm/ 3.75mm needle
notions: one sewing needle, 2 markers