Thanks for choosing health care magic for posting your query.
I have gone through your question in detail and I can understand what you are going through.
Symptoms of being slow and unorganized are the signs of ADD which may persist during adulthood as well. It may not be MS as the symptoms profile is different. Probably he has a cardiac problem which is not letting him gain weight. This cardiac problem also can lead to these twitches and lip smacking during sleep. You should get an Echocardiography
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Dr. Srikanth Reddy M.D.