There's this guy in one of my classes that also stutters... advice?

There's this guy in one of my classes that also stutters... advice? There's a guy in one of my classes (100+ students) who seems to have a stutter, and tends to use "like"/"uh" and repeats. It's probably not too obvious to others that he has a stutter, but I have the same habit of doing that when I feel a block coming. I've seen him around but I've never actually talked one-on-one with him. We had a guest lecturer who posed the class a question and this guy raised his hand and answered it, with some mild/moderate repetition. But the people that were sitting near me were laughing at the guy and were quietly saying some stuff about him among themselves (something along the line of 'what's with this guy?'). I didn't know what to do in this situation. What would've been the best thing to do here? (Also, just want to mention that this other stutterer has so much more courage than I do. He's one of the few people that answers questions in that class. Even the thought of potentially blocking gives me so much anxiety.)