I feel I have multiple reasons. My dad has a stutter so it's genes but I don't remember stuttering as a very young kid. I had talked and sang on stage when I was like 4-5 years old. Although back then I could not pronounce R, T, S- sounds and i had developed speech rather late than a normal baby would. But I kinda remember after my grandmother passed away I started stuttering and eventually it grew into a habit. It got worse in my teen years in high school nd college.