Advice for supporting a sibling with a stutter

Advice for supporting a sibling with a stutter Have a brother with a stutter for as long as I can remember. I love him to pieces and want him to succeed. I am extremely heartbroken that most speech therapists and our mom just assumed his stutter would improve after childhood, but his stutter is pretty severe even into adulthood. He will be 25 this year, dreams to enter the healthcare industry, but is often discouraged and frustrated by difficulties with fluency. I wish I could help somehow but don't know the best way to support? I have been encouraging him to try many different things that i think might help (mostly with things that relieve stress because we have noticed stressful situations, changes in routine and lack of sleep worsen his speech). He confides in me about loneliness and difficulty making friends. Often times I worry about how he will feel accepted by peers in his graduate studies and I just don't know what to do to support him on this journey. I invite him to socialize with my own social circle but he becomes very introverted and I can tell he feels left out. I have recommended things like techniques, researching his stutter, speech therapy techniques, counseling/therapy, yoga, meditation, speech devices, focused massages, and other things but I don't want him to think/feel like he is not trying hard enough or something. Not sure how I can help him become the best version of him self. I want to research more techniques and suggestions, but I also don't want to constantly bring it up unless he wants to talk about it first. Any advice for how siblings can best approach?