Different sizes are achieved by switching yarn and hooks. 6 month size is made with Red Heart Soft Baby yarn, B & C hooks, and 12 month size is made with Bernat Softee Baby and D and E hooks.

This is an easy to do crochet pattern. It uses Standard American terminology and abbreviations

Can be make all in one color or crocheters choice

MATERIALS
For newborn to 3 months for 16 inch chest
1 - 5 oz. skein EACH of 3-ply Lightweight Baby Sports Weight Yarn such as Red Heart Soft Baby yarn for Main Color and Contrasting Color
One No. 2.75mm steel crochet hook (For Yoke)
One No. 3.25mm steel crochet hook (For Body of Dress)
About 3 yards of 1/4’’ to 3/8” wide ribbon
2 small buttons or a small amount of velcro for back closure

For 6 to 9 months for 17 to 18 inch chest
1 - 5 oz skein EACH of 3-ply or Baby Sports Weight Yarn for Main Color and Contrasting Color, such as Bernat Softee Baby
One No. 2.75mm Steel crochet hook (For Yoke)
One No. 3.50mm or Size E Aluminum crochet hook (For Body of Dress)
About 3 yards of 1/4” to 3/8” wide ribbon
2 small buttons or small amount of velcro for back closure

GAUGE
23 dc sts with 3.50mm steel Crochet Hook = 5 inches
25 dc sts with 2.75mm steel Crochet Hook = 5 inches