I'm 30 yrs old. Still stutter but now I can mask it really well. I can switch phrases really fast and I have a blocking stutter most of the time where it's at the beginning of phrases or words with certain sounds in certain situations. Most people think I got over it, but they're wrong. Maybe a little better but still frustrating. Being super relaxed helps but doesn't cure it. I find I stutter less when I people in the conversation have the concept of stuttering on their minds (another stutter in then room, stuttering comes up in conversation, etc) Anyways I thought I'd grow out of it, but I didn't. It gets better though, just not completely gone