I'm about to dive into Yankee Knitter Designs pattern #26 Roll Striped Watch Cap - one for my 3yo and one for my 6 1/2+ yo. The pattern sizes are Babies, Toddlers, Child's small, Child's medium, Women's and Men's with a note to use Women's for Child's large. There are no head circumferences or finished hat measurements listed.
The toddler size seems reasonable for the 3yo, but I'm not sure what size to use for my almost 7yo. His head circumference, if the measurement I just took while he was sound asleep
(bad Mom! ...but I think it was a pretty good measurement) is 21.5"
Thanks for any advice!