Don't get discourage by your first litter. I've got one holland lop buck that appears to carry some genetic dysfuntion where his kids seem to die. I was told it was my buck. If you can, see if the people that you got her from have a buck that she's bred with before and breed her back to one of them, if all the kits are safe and sound, then I would suggest a new buck.
Gabe, my holland Buck. He's had two litters, first one was 2 to skye and the second litter was 3 to angel. out of the five, two are still alive, one from each litter. while angel's could have been her, she's not that great a mommy, i own Blaze (my avatar bunny) and I've never had a problem with his kids and angel is blazes sister. skye's baby to Gabe just dropped dead one night on me for no reason, the other is a happy pet for some under privileged child that wanted a pet but couldn't afford a dog, so i gave him the other baby. The last one of angel's litter is her doe and i've got her. she's proving to be difficult to show/breed but i'll manage.