Hi amy and welcome to the Chiari forum......
I am not able to give you the perspective of a parent with a child going thru this, but I did go thru the surgery myself if you find that helpful let me know....
Post op, she may feel fine and want to do more then may be good...the pain meds leave us feeling so much better then we have for so long we try to do things too soon and this can cause set backs...so keep her occupied with things like coloring or listening to audio books...that one was the best for me...it allows our brains to heal....not using any part of it to do anything and it is a trauma to our entire body and just using our eyes to watch TV can be a strain......it takes time to heal, so rest, rest and more rest is the best advice I can offer for her.
If you have any other questions let me know.