Funnily enough, you’re already using the best resource you can: him! I personally had to have the discussion with my wife that I don’t want to be touched, because although it’s soothing it makes me feel like something is wrong. There’s nothing wrong with stuttering. It’s all so individual and you’re on a great trajectory to supporting him. I’m getting more comfortable with disclosing, but if it’s a social situation planned from your side maybe pre-emptively telling people that he has a stutter before you bring him around could help. I personally haven’t been mocked, save for once by a 6-year-old that was more curious than being malicious, but wondered why I talked like that then did a picture-perfect recreation of my stutter, which stung.  But, honestly, people have just been more confused or curious than harsh and malicious. It’s possibly just confusion around what’s going on, hence disclosing the stutter may help alleviate this outcome.