I believe most Little People have the hypopituitary form of dwarfism. They basically don't produce enough HGH from the anterior pituitary to grow to their otherwise genetically determined stature.
However, there are other forms of dwarfism with different causes. The release of HGH from the AP is controlled by several other hormones and so a failure in any of these systems could theoretically produce dwarfism, or a failure of the body to respond appropriately to growth hormone. I guess you could even have cases where the growth hormone receptors on certain cells are non-functional. Growth is a complicated topic.
My real point, however, was that the name Midget is generally regarded as pejorative. Imagine someone marketing melanistic cal kings as "n****r kings". I think the same offense could be taken from the term "Midget Indigo".
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Chris Harrison
San Antonio, Texas