A cute sweater with a checkerboard hearts pattern.
Buttons at the shoulder (requires 6 buttons).

3-6 months size uses 4 balls of yarn (1 A, 2 B and 1 C).
6-12 months size uses 4 balls of yarn (1 A, 2 B and 1 C).
1-2 years size uses 5 balls of yarn (2 A, 2 B and 1 C).
3-4 years size uses 6 balls of yarn (2 A, 3 B and 1 C).
5-6 years size uses 7 balls of yarn (2 A, 3 B and 2 C).

Stitch holders also useful.