cutting as much as it is part of the game does hold some dangers for younger athletes
5lbs isn't too much to recover from teens have good recovery
just monitor your niece a little she is prob small and 5lbs
might be a larger percentage of her body weigh then we might think.
Cutting for female athletes is different
lets say there is more going on hormonally with
bodyweight fluctuation like cutting and caloric restriction with women vs men
particularly when they might be at a very low body fat
as for foods pedialyte cut with water is a good start
followed with water
I am a big fan of baby food for a fast way to reintroduce foods and
simple carbs back into the body.
I've seen off brand pedialyte style freezer pops that would be a good idea
banana works here too so does yogurt
I used to do some kind of gator aide type drink
water, baby food , yogurt , and fruit , maybe a baked sweet potato or baked potato
stuff that was easy to eat, and did not have allot of acid
if it was a tournament I tried to rehydrate , get some simple carbs in
take some short naps if possible, and work back into more solid foods as the day went on.