It all depends on the person who stutters and how comfortable they are with talking about it. For a long time, I did not feel comfortable talking about it at all, with anyone, even friends and family who have known about it my entire life. Whereas, in the last couple of years, due to some great people in the stuttering community, I have become very comfortable talking about to the point that I bring it up when I can to ease awkwardness in situations. I would give the advice to feel out first how comfortable they are talking about their stutter. While maybe slightly taken aback at first, I think it is a great compliment and not one I hear very often.