she's now purging all, and probably will continue for a while - now it is very important to keep her hydrated, and add minerals to her body.
Maybe some fresh veggie/fruit juices, light broth, water with a very little bit of salt. At such a young age dehydration can happen very fast. She may also benefit from a little warm water with honey if you have that.
Maybe you'll consider this (after the blockage has voided):
When I was a child, when we were recuperating - they would: toast a little rice on a pan till brown (not burned), then boil it and give us the water.
it a) tastes delicious
b) suppossed to re-mineralize
Now I see they sell "toasted rice tea" (don't know the name) in asian markets.
I'm sure others will pipe in with suggestions for her gentle return to normalcy.
[Id say 1/4 cup rice to 2 cups water let boil for 5-7 minutes]