Babies are behind...

Question
I had an unexpected litter of babies three weeks ago tomorrow. I have concerns that they are either developing slowly or under developed. Although they are almost three weeks, they still have not opened their eyes and fully unfolded their ears. They are not as curious and explorative as they should be despite frequent bursts of handling, as often as we feel comfortable taking them from their mother. She is spending more time off the nest, and they are slowly beginning to venture a few steps away from the nesting area, but I can't help being anxious about their size and development. I am a first time rat grandma with no experience in raising babies! I hope you can let me know if this sort of delay is normal and acceptable, or if I should get them checked out or something. Thanks so much for your time and help.
                                                           Mayghin

Answer
I think they are ok to be honest. They are not yet three weeks of age so they are still going to be unsteady on their feet and wobbly. The ears will end up sprouting up soon, there is still time yet. They are starting to move around and thats good. Some babies may be slower than others. Are they wobbly yet?  They still see in a haze so their vision is not really keen, well....thats a dumb thing for me to say since rats have lousy vision anyhow, but as pups its real bad.  

What about fur?  Has that come in yet?  It should have unless you have hairless or even rex rats.