I've taken speech therapy and it mostly helps with guidance. It's up to the person to do the work on their own time. One thing I try to do everyday is read from this word list: https://www.home-speech-home.com/speech-therapy-word-lists.html Tips: 1) Breath from underneath the diaphragm 2) Take a 2 second inhale through the mouth before speaking. 3) Don't be afraid to stop mid sentence and start over again (Remember to breath). 4) Don't leave to much space in-between words. Link together every word in the sentence like a chain. 5) Try reading in unison (It might be tough at first, so start with short sentences). Also I believe there was a recent post about the benefits of this. ([Link](https://www.reddit.com/r/Stutter/comments/xq5f4v/what_are_your_thoughts_on_this_research_choral/?utm_medium=android_app&utm_source=share)) It's hard not to get frustrated. Always remind him that it's not as bad as he thinks it is. Also he is not alone.