The older rabbits have lots of material scraps to tunnel in and they are fun to watch. I provide a quiet environment. I keep my cats away and my children away from the rabbits so they don't get used to them. Dietary requirements are very important. Rabbits need a high protein diet due to having such a rapid metabolism.
Protein is a longer lasting energy source.
In an emergency I will use goat's milk. The vitamin substitute I use is Diamino 4X, which can easily be obtained from a vet. I feed them with a dropper. They are fed every 2-3 hours from early morning to dark. Once the rabbit's eyes are open, I start mixing plain yogurt in with the formula to help prevent intestinal bacterial infections which can cause diarrhea.