my son has gastroenteritis and i hate seeing him like this. he has already lost a pound. they told…

my son has gastroenteritis and i hate seeing him like this. he has already lost a pound. they told me to keep him on fluids yesterday and then tomorrow try him on fluids and food. He had french toast sticks yesterday and a full nights rest. He had oatmeal for dinner and again at 1 a.m. in the morning he wakes up crying because he is throwing up. she said 3 days keep him on the b.r.a.t. diet and i am scared because of the lack of eating. he is so scared he gonna throw up he will not eat anything. Is there anything other than rice, bread, applesauce, and fruit he could eat? I need some help because this is the worst and im worried