Basic pattern for a top down raglan baby cardigan.
Requires knowledge of UK double and treble crochet.

1 ball needed for the smallest size, with short sleeves.
2 balls needed for smallest size and 3-6m with long sleeves.
3 balls needed for 6-12m with long sleeves
4 balls needed for 1-2yrs with long sleeves.

Pattern can be adjusted for larger sizes, and other yarns can be used too. It would work well with a fine aran or worsted yarn.

NOTE: the cygnet merino is a thick DK yarn. If you are using a fine DK then use a 4mm hook and follow the next size up to achieve your desired size.

To make bigger, work more rows before the armholes, until the chest is your desired measurement,then add the armholes.