Sorry, I had trouble seeing the pic, my 'puter does that sometimes. From my days as wildlife rehabilitator, I remember that very young rabbits were cleaned by mom after feeding, they need to have their anus wiped to stimulate defecation, otherwise they become impacted with fecal matter, stop feeding and die. Not sure about the age of yours, but if it appears young and not pooping or not eating any more, a soft damp rag/washcloth to the bum should do the trick.
Over-feeding/aspiration is the downfall of most baby rabbits.
Wild rabbits don't normally get their water by drinking, they get it from their Mother's Milk, their food or the dew on their food.
The less human handling the better for his survival, when released back into the wild.
Good luck with Lucky.
I know this is not your case, as the mother was killed, but most ppl 'find' baby bunnies and think them abandoned/orphaned. When in fact, the mother only visits them in the nest once or twice a day, until she goes to them for the night. Ppl unknowingly take babies from their mothers.
