I have a couple books on herbs and herbal remedies. One tea recipe I came across was...
make an infusion of the following herbs:
1 oz. chamomile
2/3 oz. peppermint
1 oz. caraway seeds
2/3 oz. angelica
Use 1 tsp. of the mixture per 1 cup of hot water. Steep for ten minutes and strain.
Other herbs that are listed as good for the tummy:
Anise, echinacea , raspberry leaves, dong quai, catnip (or catmint), lemon balm, fennel seeds, calendula, spearmint, and of course GINGER is probably the best and most well know digestive aid.
Alot of these you can find at the grocery store, the rest at health food stores.
Hope she feels better!!