hypotonia

Most of these children presented with hypotonia, lengths and weights below the third percentile, and psychomotor retardation that improved with the appropriate nutritional supplementation (24).

So I wonder if one of the benefits here of strength training or just building muscle mass in general is that it counters hypotonia.

Kabuki is multi-system affecting, often accompanied by heart disease, feeding, hearing, hypotonia, endocrine, limb/spinal/skeletal/organ abnormalities, and similar to Kleefstra, intellectual, speech, and mobility difficulties.

I'm sorry, but this is utterly absurd - you are talking about things that are factual; it is not a fact that people with Down's Syndrome are happier than other groups, neither do related physical differences (facial features, hypotonia, heart problems, whatever) them happy.

Kabuki can and has affected multiple organ systems with our girl, she has very complex heart disease, a pelvic kidney, hypotonia, hip dysplasia, malrotation, right isomerism, asplenia, immunodeficiency, endocrine issues, severe hearing loss etc, etc.