Well, it differs a lot per individual. What i can do is tell you what happened with me and draw your own conclusions. ​ Long ago, when I was still young, I would never really talk. I started talking to others since the 3rd class in elementary school (I live in the netherlands). after that, I never really stuttered, until I hit age 11/12, just when my puberty began. I stuttered for a very long time, exactly knowing what I wanted to say but just unable or struggling to get the words out there. I kept struggling until I was around 18/19 years old. At that age I decided to go see a therapist and I spent more than a year in weekly therapy. I'm 21 now and for me, it has all payed off. My puberty is slowing down and so does my stutter. It still exists, let me make that very clear. But I dont have it in every single sentence anymore. ​ as for your case: well, that's basically what happened to me. it could be your brain growing, causing disruptions that normally wouldnt occur. It could be something that stayed or that fixes itself. It's hard to predict, really. about the second thing: Welcome to the c-c-club! I wouldnt say it is harmful behaviour to evade certain words, but just keep monitoring it really closely. Sometimes it is better to learn how to overcome a stutter rather than to evade it. For example, when you have to say your birthday, you cant evade that. you simply cant say "somewhere in August" when a cop asks you your date of birth, or when you have to choose between A or B (of course you can work around this by saying "the one on the right" instead of B but you get what I mean). ​ Personally I would advice to keep monitoring it and to keep talking with your parents about your stutter. Just see how it develops over the course of, say, a year. If after a year it really becomes a problem for you, you and your parents can consider taking you to therapy (unless you can pay for your own therapist like I did). ​ EDIT: I also want to be very clear what stutter therapy is about. Stutter therapy IS NOT ABOUT MAGICALLY REMOVING YOUR STUTTER! During stutter therapy, you learn multiple ways how to handle the stutters that you experience. If you know that you struggle with a certain word, for example "cookie", you can first try to say it slowly. coo-kie. If you cant really do that, than try to take a deep breath, reach a calm state of mind and say it again. cooooo-kie. if you still struggle with the c and the k, try throwing in some other letters that softens them up. for example, try saying chooo-khie (not like a train goes choo choo but a c morphing into a more soft h). what you will notice is that things will go much better if you try to soften the harder sounds. (do it with care, otherwise people will think you're speaking unclear). ​ Another thing a lot of stutterers tend to do is to run out of breath without realizing it. to fix this, try to stay calm and to consciously breath in after every sentence.