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All of the conditions you describe with your daughter sound identical to
those of my cousin when he was a teenager, with exception that he was not
celiac.   He was and is an extremely picky eater--refusing, above all, milk.
  He had tremendous bone pain during his adolescence, all the while refusing
to eat at all correctly.   It is my opinion that he literally did not grow
correctly as a result.  He is extremely skinny, given his height.   He is not
robust in health.