These instructions may be used for either of the 3 sizes. Check yarn and needles for size you wish to make.
(Pictured is infant in maroon and size 1-2 years in white.)

Materials:
Infants: 3 ply baby yarn - 3 oz
2 Pairs size 1 knitting needles

Size 1-2 years: Sport weight yarn - 4 oz
2 Pairs size 2 knitting needles

Size 3-4 years: Worsted weight yarn - 5 oz
2 Pairs size 3 knitting needles