Not totally related to dyslexia, but I had a severe stutter in English (my native language) as a child but have never once stuttered in Spanish (close-to-fluent for about 10 years of my life, though I am rusty now) or German (beginner, but I lived there for a while and spoke conversationally daily). This has always intrigued me because it feels like magic to me when I don’t stutter in foreign languages. The only explanation I have is that my stutter was possibly exacerbated by my public speaking anxiety as a child, something I grew out of rapidly while maintaining a bit of the stutter.