Thank you for chiming in!
Thanks to all of you for sharing your experiences and suggestions.
We had not much success with early group swimming classes, even with me or a one-to-one aide for him. it was all too much: having to get changed with other people, the noise, the stimulation, the anxiety, water in your face, echoes....it's very very tough for kids on the spectrum or with any kind of sensory issue. Plus DS is underweight and has hypermobile joints and basically, sinks like
"My definition of housework is to sweep the room with a glance"
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My kids are a good bit older now, but I remember those days......
Don't worry too much about the prognosis of not being able to attend a swim class at age three.