PLEASE HELP!! BABY ROBIN FELL OUT OF THE TREE AND IS INJURED!!!!?

so yesterday we found a little fledgling bird, a robin, my dog bit it, so the wing is kinda messed up, and we called the wildlife rescue league, but they didn't call back yet since they start working at 9 am. so until then, we were wondering, what should we feed him, Disney? the parents are flying around, but he can't fly cuase of his wing. what should we do? thank you! and please hurry up, he's realy hungry!