I was recovering recently from a high fever and found that once it broke, some of the carb and sugar cravings I hadn't had for months had returned. Sometimes your body does need a refeed, when it's burned up all the glycogen in your muscles, so some GOOD carbs and starches aren't a bad idea. I made use of sweet potato noodles (get them at a Korean food market, they're called "chap-cheh") in chicken and beef broth and they worked wonders.
Best of luck to your son in his recovery, glad they caught his appendicitis in time!
If you want to reach the end of the trail, first you must find the beginning.
If you want to be strong enough to walk the trail, trust your feet.
If you want to go fast, go alone - if you want to go far, go together.
6'0" white female, age 24
Pre-paleo: 247.8 lbs
Current weight: 212.8
Goal: 199.9 (and to rock a two piece bathing suit surfing in Costa Rica this November!)