If they don't have it on hand they usually do their best to order it for you, but you may have a wait depending on how hard it is to find.
Most likely if its not in stock, they'll keep your name and phone number so once it comes in they can call you back and you can pick it up.
Jawbreaker is crowdfunded. Not available in comic book stores. So no, CBH would not have this one. FYI, the book is a response to the SJW influenced Marvel & DC creations. It's not a left or right leaning story. It's simply meant to show independent writing is needed. Think about Marvel and DC is doing like a disc jockey being forced to play a specific song by the radio station and finally the DJ gets to go to work for another radio station where you can play the songs he wants. But to be honest with you I think your son is just a Speculator and wants a copy of this book because it might be valuable later.
You might want to do more research about the specific title. Not all comic books are designed for children. I don't know how old your child is, but you should know what he's reading rather than just buying him anything that he shows an interest in. Sorry to sound preachy. But I am a former comic enthusiastic and I know as a child I was reading things my parents would highly disapprove of. Just a quick search on Google with the keywords jawbreaker and comic should provide you with so the information you need.
If it is a comic or comic related they are your best bet
Thanks! Your answer is awaiting moderation.