This cute girly romper is made using a simple single crochet and the primrose stitch for the skirt and front bib.

Materials
dk / weight 3 yarn (I used Drops Cotton Light 50 % Cotton 50 % Polyester 105 Metres per 50 grams)
4.5 mm hook

Preemie 230 metres
Newborn 280 metres
0-3 Months 330 metres
3-6 Months 400 metres
6-12 Months 480 metres
1-2 Years 560 metres

Written in English US terms with abbreviations for UK

Pdf is 28 pages with each size written separately and has plenty of pictures.