I have egg and peanut allergies (and milk as well!). My parents found a couple of cookbooks for people with allergies. For egg in recipes try adding extra baking powder instead of the eggs, that way you can can make waffles and pancakes. Please let me know if I can help you in any way.
All I ate growing up was soymilk on regular cold cereal. As an adult I have found cornbread and muffin recipes that I like but what I mostly eat to this day is still soymilk on cereal. Maybe you could try some fruit compote dishes or applesuace as well. I will look up the name of the allergy cookbook when I next visit my parents.
I don't know if you will be able to ever make any kind of egg sandwich for her. I've heard of substitutes but I ahve never used any of them.