A small cake just for her to dig into is great with a larger one for everyone else.
Keed the food in mini size since it's for little kids. Mini cupcakes, little cookies, mini ritz crackers, chicken nuggets, tator tots, etc.
If you are really creative you can decorate sugar cookies to look like faces with hair, etc for each of the guests. You could also decorate small food items to look like ladybugs, bumble bees, or other cute insects.
It all depends on your theme, your budget and how much time you want to spend.