It is very much a case of letting nature take its course with mum and babies. My bun gave birth to 6 babies and luckily all survived. The vets told me that if the nest is touch the mother will feel threatened so she often kills the babies for their own protection. In the wild rabbits should probably be left alone.

I also agree that a vets should be called, theats the best advice I think

Good luck and let us know how things go.