Strongly seconded - even if we ignore the political aspects of 'fluency' and construction of normalacy treating the child's speech as normal and encouraging them to speak regardless and that if people are mean to them then those people are the problem will be extremely important. I'm completely understandable in every day speech, and that's with my stutter and that only came because I did the work of normalising that. I wish it was done when I was a kid. It is worth reading around the concept of [stammering/stuttering pride](https://stamma.org/features/what-stammering-pride) as well even if 'pride' isn't a word you'd necessarily apply. I don't, but the idea of normalising stuttering is good.