Wondering

I do want to focus on crocheting hats for babies, however, I'm wondering if, since we're crocheting hats for babies with Hydrocephalus, should we include adult-sized hats as well? Since it's hard to determine how big a baby's head will be (due to the Hydrocephalus), maybe we should include all sizes? I just don't want us to crochet and send hats that end up being too small, and therefore unuseable. What do you all think?