Yes. A deaf person thinks in American Sign Language, or whatever language they “speak”. Since they can read words, they’d be saying it really loud if they aren’t completely deaf. I had the Same question the other day and whenever they think, they think in sign language. So I’m guessing if the kid happened to be deaf, he wouldn’t be 100% deaf and just speaking really loudly to hear himself. If they were, they’d be able to think/read in there head.
Sorry for the long answer. Just thought I’d explain it instead of just saying yes!