I also am concerned about your afternoon crash. It probably is sleep apnea, but don't overlook hypoglycemia also. My daughter used to put her head on the table while I was getting dinner and begin wailing and then sometimes fall asleep. Making sure she got peanuts or some other SLOW sugar release type of food mid morning and mid afternoon made a huge difference. And, sure enough, her daughter started that high pitched wail at about the same age! The snack, if it isn't sweets, takes care of their problem. Yours sounds more complex, but don't ignore the "sugar crash". It has such a simple solution. Good luck!