The symptoms of mono can last for anything from 2-4 weeks. For a fever or sore throat that can last as long as 2 - 4 weeks also. However, if it involved enlarged lymph nodes or spleen then that can last for a few weeks longer still than as above. The fatigue and wanting to go to bed early are all part of it. As it is self limiting, the more rest that she can get the better really. I have heard of fatigue and weakness lasting for weeks and sometimes even months in some children so I would really encourage her to rest heaps. You were wondering how long she would have had the virus. If she has it now then you could say for kids that they incubate the virus for up to two week before the symptoms and then some kids have no symptoms at all. Is she CAH and have you given any stress doses at all? What has the Paed said about that? I was just wondering if she has reflux why that is. Does she get that in the evenings when she lies down in bed. Another way to help with that is to prop her head up with an extra pillow if that is what is happening. If it is when she is upright then she really needs to be checked out by the gastroenterologist. I presume xantac is an antacid? My fourth child had reflux as a newborn for six months and for the first few months whilst I breastfed I had to give him infant gaviscon before feed times as he would bring the whole lot back projectile several times per day at first. That was related to him being born premature though and his gastrointestinal track was a little immature at first. After a while that fixed itself. Sometimes when there is pressure on the stomach or upper gastro area, it causes reflux (like in pregnancy) but I would not like to guess why your daughter has the reflux. I hope that you get your appointment soon and get to the bottom of it anyway. The best thing you can do for her at the moment is plenty of rest and give her a tonic if she has lost her appetite. That and the antacid stuff. Regards Val