FWIW, ADHD in the stuttering community is atleast 2x prevalent than the general population. I forgot the exact figure, but I read one study that said ~50% of stutterers met the criteria to be evaluated for ADHD. So comorbidity is possible. As a parent of a child who is also globally delayed, I feel like if the neurodevelopment is affected, it's very plausible that it can be both. Isn't that why they call it global? lol. Mine has apraxia, stuttering, and adhd, et al. The stuttering has increased more recently. I stutter and have adhd.