i'm not deaf or anything but i have watched and read a lot of media about deaf people or stories. My one flaw on this is that while it is impressive that the actors learned sign language i feel like the director should've done more research on deaf people. If they have been deaf for quite some time they should be able to pick up on reading lips and etc it surprised me how his family immediately turns to the son to interpret what the person said. Also I thought if you lose your hearing mid in your life you still should try to maintain speaking so it surprises me how the father can't saying basic words or doesn't try to, at least with his son.