How do you ever feel any better after losing a beloved pet?
Yes. It’s the one thing pretty much guaranteed about owning and loving pets; you are going to loose them, one way or another. Yes it hurts, allow your family to grieve the loss of your pet and let time work its healing magic. Time really is the only thing that lessens the loss of a loved one, whether human or animal. Talk to your son about life and death; he’s old enough to understand; explain that the bunny was old and that he’s gone to a beautiful place where he is young and happy and will wait for the time when they can be together again many years away. You can call the place Rainbow Bridge if you like. Be strong for your son and you will also be helping yourself.