From the Knit Rowan website:
Knit this adorable baby cardigan, a design from the Rowan archive originally featured in Classic Babies. Designed by Martin Storey using Baby Merino Silk DK, a luxury machine washable yarn designed specifically for babies (merino superwash wool and tussah silk), this soft button up cardigan is adorned with fluffy chick motifs.

Baby cardigan with raglan sleeves, crew neck, buttoning up the front, with moss st edging. Two fuzzy chicks are knit separately and sewn onto fronts; embroidery creates additional details like chick legs.

SIZE
0-3 [3-6, 6-12, 12-18] months
To fit chest 41 [46, 51, 56] cm/16 [18, 20, 22] in

YARN
Baby Merino Silk DK and Rowan Kidsilk Haze
A DK Opal 673 4 [4, 5, 6] x 50gm
B KSH Meadow 581 1 [1, 1, 1] x 25gm
Oddment of contrast colour for embroidery
Use Kidsilk Haze DOUBLE throughout

NEEDLES
1 pair 3¼mm (no 10) (US 3) needles
1 pair 3¾mm (no 9) (US 5) needles
1 pair 4mm (no 8) (US 6) needles

BUTTONS – 6 x small

TENSION
22 sts and 30 rows to 10 cm measured over stocking stitch using 4mm (US 6) needles.