Hi! Sorry to hear about your daughter's allergies. It's going to be tough taking out wheat (I'm really surprised she didn't test for gluten intolerance, which would be no wheat, rye, or barley) and corn and oat. And no eggs. Which means you will need to homemake/bake her bread. You can substitute flax seed for eggs.
You need to go to your local bookstore or even to their online site and buy/order a subscription to the magazine Living Without. It is a magazine specifically for people with food allergies and intolerances. They have wonderful articles and lots of recipes. The best thing is, the recipes will oftentimes give ideas for subsituting this for that (so you can get rid of your allergen if it happens to be in the recipe) AND they have a wonderful section in the back that offers all types of food substitutions. Every couple months they usually have a section where they'll highlight some food recipe ideas for children. And the Living Without Web site has a ton of recipes--I love going there!
You'll have to start experimenting with different types of flours, like teff, sorghum, amaranth, millet, quinoa flour (also quinoa itself, which tastes really good made as a pilaf with small bits of meat and veges), rice (white and brown; brown rice will give her wholegrain and is better to use, as it won't raise the glycemic index like white rice does), buckwheat (despite the name, it is NOT wheat; it belongs to a grass family), arrowroot flour, almond flour (oops, forgot she can't have tree nuts; delete this one), different types of bean/pea flour (like chickpea/garbanzo), chia flour, hemp flour, potato flour, potato starch flour, tapioca flour. Wild rice is actually a type of grass and is excellent when used in a pilaf.
Basically, given the foods/grains/flours she is allergic to, you pretty much want to stick to the different grains/flours that people with Celiac disease/gluten intolerance use. Just be careful buying prepackaged food/kits, as corn is substituted quite a bit (but not as much as rice. I feel for those who can't have gluten or rice).
I like peanut butter in stuff but not on toast or bread (I was never a good P&B candidate because I hate eating it! LOL). I absolutely love almond butter. I have tried the ones made with sunflower; I don't care for them. A little too salty for me. There are so many different types of nut butters... except she can't have tree nuts. Rats. Yeah, then I'd try to get her to like sunbutter.
I know how you feel. When I was 40 years old, I finally discovered all the foods that were making me sick. The ones that were the most important were gluten intolerance (meaning no wheat, rye, barley; oats if they are gluten free), casein allergy (no cow milk; substituted goat and sheep as well as nut milk alternatives), soy intolerance (no soy). And I also had another 21 intolerances that were mild, moderate, and severe (most of those ended up being to fish that I have never eaten, so that does make it easier. But banana, apple, almonds, black pepper, celery, spinach, etc.--I eat all of them and love them! But after the gut heals, you can, after awhile, usually eat some of these "forbidden" foods on an occasional basis, which is what I do. I miss bananas for their potassium and quick pick-me-up, and apple is, like in every juice imaginable! I no longer drink juice.)
Your daughter will cry and kick and scream and give you a hard time. She's young and doesn't understand that the foods she loves/is eating right now are what are making her sick. She will adapt. Just do the best you can with what you have to work with (without). And visit the Living Without Web site for some recipe inspiration. You might even be able to send them an e-mail and give them the foods your daughter was recently diagnosed as not being able to have. They have professionals on their panels who should answer and give you some food ideas as well. It will just take more time on your part to think/make/put together new meals.
Good luck. I feel for you and your daughter. But it's good to know what she can't have so that you can help her heal. And there are many, many other foods out there to eat. She'll just have to acquire new taste buds.