3 new buns-1 dead, 1 sickly, 1 fat and sassy

Question
Our female rabbit gave birth to her 2nd litter a few days ago.  Her 1st litter she had 2 buns that lived (one is the dad to the new litter) and 2 were still born. With this litter she had 3 babies total over the course of a couple of days.  We checked her nest yesterday and found 1 bunny had died.  This morning we took the other 2 out for the first time to get a good look at them.  1 bunny, presumably the 1st born is covered in fur, about 4 inches long and obviously well fed.  The other bun is very scrawny and little, still all pink with no fur.  It's about 1/4 the size of it's sibling.  Since 1 bunny already died should we assume they might have more serious health problems and the other runt probably won't make it either?  If runts are common and there is a good chance we can nurse it to health on our own (if mom just isn't feeding it) we will certainly give it a shot, but if not and mom isn't taking care of it because she knows it's not healthy we might just let nature take it's course and see what happens.  We can't afford to take it to the vet but we certainly don't want it to suffer either.  

Answer
Dear Maureen,

You don't say what breed of rabbits these are, but if both parents are dwarf rabbits then there is a statistical likelihood that 25% of them will be born with a lethal genetic condition known as "peanut."  There is nothing you can do to save such a baby, as they simply are not viable.

The problem is not unlikely due to the parents being so closely related to each other.  Mother and son will likely share a number of harmful genes, but since each rabbit has two copies of every gene, they may have a "good" copy to mask a "bad" one.

If mother and son mate, there is a 50% chance that each one will pass a "bad" copy to the offspring, and if a baby gets two "bad" copies of a particular gene (such as the one that causes lethal "peanut" in rabbits), then the baby can be very sick or just inviable altogether.

If you suspect the mother is not feeding the baby, you can try raising it yourself with the instructions here:

www.bio.miami.edu/hare/orphan.html

I would strongly urge you to read these articles:

www.bio.miami.edu/hare/breeding.html

and especially:

http://www.rabbit.org/faq/sections/spay-neuter.html

For the health and longevity of your rabbits, you need to do the right thing.  You can find a good rabbit vet here:

www.rabbit.org/vets/vets.html

I hope this helps.

Dana