I am not a speech language pathologist, nor have I ever studied stuttering beyond an intro to communications disorder class in college I took for credit and because I was curious about my stuttering. Do I think it's all in my mind as in I "made it up"? No, not at all, and I don't think you're implying this either to be clear. Sometime speech impediments can be the result of the brain "making it up.", creating a disorder when there is not one physically present in the moment, and making it either manifest, or become physical as the brain re-wires itself. I think it's a literal mis-wiring or mis-firing in the brain or along the circuitry that controls our fine motor movements in many cases from youth. So yes, it is in our brains in many cases. I can not speak for cases where someone develops a stutterer as the result of an injury or damage, especially when there may not be any sort of clear evidence. What you describe about your Mother's extended hospital stay makes me think your stuttering in particular could be based in that fact. I don't know if it would be proper to call it trauma, but to a 3 year old who has a new sibling taking their mother's attention, plus an extended absence of their Mother - that all could be trauma from a situation that could incite fear, anxiety and worry in a small child. Given that the brain is still developing so much at that point, there could be a change in wiring that occurred somewhere along the speech pathways. In my personal scenario, my family never described any sort of situation that could have been the 'start' of a stutter. I think mine was more of I started stuttering and then perhaps the teasing I received made it stick? I don't recall being an anxious child, but I am certainly an anxious adult and my stuttering comes and goes in severity accordingly. The past.. maybe 3-4 months have seen an uptick in stuttering and new blocks, repetitions, and elongations on sounds I didn't do them on before. In my case, maybe the stutter was always going to start?