This pattern is for a hat for a baby. Baby head sizes vary, but this hat is generally stretchy because of the ribbed band at the brim, and is a one-size-fits-most. You can always go up a needle size for a slightly larger fit.
This hat is knit in the round on size 7 double-pointed needles using Aran/10-ply yarn.
You can make it in solids, stripes, or variegated yarn, and you can omit the ears for a regular, non-animal hat.