I clearly remember being fluent. When i was 5 I started stuttering seemingly out of the blue. I had this teenage neighbour girl I spent time with who stuttered so my siblings believed she gave it to me lol. My 8 year old nephew also started stuttering around the same age after being fluent (this time _I_ gave it to him). It's painful watching him become more and more reclusive because he's so self conscious about it. I'm in my mid 20s now and it's much better than during my teenage years, when I was functionally mute for a while. I'd say I have moderate stuttering with occasional severe spikes when I'm emotional. It's also worse in my native languages than in English. I never received help of any kind, but the more my overall self confidence improves, so does my fluency. But generally it's been very difficult growing up as a stuttering girl.