Hey I also speak multiple languages (3 to be exact). My mother tongue is Punjabi but I moved to the US at the age of 5 and English quickly became my primary. I usually stutter more while speaking Punjabi than English.. so much so that most people think I don't know my mother tongue very well but the opposite is true. I often find myself correcting the grammar of my siblings (they don't stutter) in Punjabi. When speaking to my Punjabi friends here in the US, I often switch from English to Punjabi and Punjabi to English because that somehow reduces my stutter. I read somewhere that people who speak multiple languages have multiple personalities (one attached to each language) and I believe this is true at a subconscious level too. I also learned a little Spanish and when I spoke that with my Colombian friends, I stuttered very little. I guess we unconsciously become accustomed to stuttering with our primary language so that when we learn a new language, we may "forget" to stutter while speaking it. Now what I do to counteract this? I practice speaking in the language in which I stutter the most, which is Punjabi. I often read Punjabi books out loud to myself in a slow and controlled manner with proper breathing techniques until my stutter becomes almost non-existent. I guess this exercises my speaking and my stutter becomes minimal in both Punjabi and English. You need to do this on a daily basis though. I don't think you should give up on Portuguese or Brazil because you would basically be running from your past and yourself. You probably have been stuttering from a small age so you probably associate most of your stuttering with your first language. You just need to get a new outlook on this language, but don't run from it. Because if you do, if you ever start stuttering in other languages, you might consider running from those languages too and soon you'll have very little languages you feel comfortable speaking. Plus, given that Portuguese is your mother tongue, you probably think and speak to yourself in that language. Suppressing that could cause internal turmoil for you.