This is a very interesting observation. It seems to me that you started stuttering in 2021 during COVID right? Did you at any time contract COVID during this period? Since your brother has a stutter himself, you’re genetically predisposed to stuttering too, although you might not have the neurological condition as strong as he does. Both my brother and I stutter. His was much more severe than mine, whereas mine was milder. It has been reported of people temporarily stuttering during COVID due to “COVID brain fog” and other anomalies in the brain during that stressful period.