We purchased the 12 month size lavender birds and flowers design for our 8 month old daughter (who is 50th percentile in head circumference/ height/ weight), and she is adorable in it! We're still folding up the bottom of the hat (unfolded the hat is long and falls over her eyes), so there's definitely room to grow.
It's been cold out lately so we usually put this hat on (covering her ears) before putting on her jacket or vest's hood. The material of the hat is also perfect for shading her eyes when she naps in her car seat. Cool added bonus that we weren't anticipating!
We love our little purple birds and flowers hat. Not overly girly, very soft and pretty roomy for our large domed kiddos.