I was looking over my most recent Dumbo BEW litter and noticed one little guy has not opened both eyes like everyone else, one seems to still be stuck closed.
Here is video of him:

There are other things that concern me as well, the overall shape of the rat seems a bit off, the head is a bit larger and the body a bit smaller than the others. Also, he seems to have a bit of trouble walking in a straight line.

I'm guessing these are just unfortunate birth defects?