For this pattern you will need (100g Balls) :

Sweater with Collar, Sweater with V Neck and Cardigan:

0-3 months (16in Chest) - 1 Ball main colour A, 1 ball contrast B, 1 ball contrast C.
 3-6 months (18in Chest) - 1 Ball main colour A, 1 ball contrast B, 1 ball contrast C.
6-12 months (20in Chest) - 1 Ball main colour A, 1 ball contrast B, 1 ball contrast C.
1-2 years (22in Chest) - 2 Balls main colour A, 1 ball contrast B, 1 ball contrast C.
3-4 years (24in Chest) - 2 Balls main colour A, 1 ball contrast B, 1 ball contrast C.

Needles Needed: 3.25mm and 4mm.

5(6:6:7:7) Buttons for cardigan.
1 Button for sweater with collar.