[header] How to feed baby rabbits [title] Confirm that the mother is not feeding the kittens. [step] Before you take a baby rabbit away from its mother or think it's orphaned, make sure the mother is not feeding it or that she is a risk to the kitten. Mother rabbits feed their kittens about twice a day and only for five minutes. 
The babies also do not need the mother to keep them warm. If the babies do not seem distressed, even if the mother is away from them a lot, the mother is likely just taking a break and you should not interfere.