At long last I have some shaded kits in nestboxes. Two seal Rex does, both bred to sable bucks delivered 7 kits each recently. As newborns, they look nothing like what final senior coat color is, they seem to morph through a variety of sepia shades along the way as they molt from baby coat, young junior, junior prime, and finally senior prime.
When litters arrive, I wait until mom finishes cleaning the kits and hops out to clean herself up. I then remove the nestbox, look for and remove any dead kits, afterbirth, and soiled hay, and do a head count with pics for recordkeeping. I add fresh hay and extra fur if needed, tuck them in, and place them back with momma, and give momma some kale, banana, or other treat.
The 3 lighter ones in the photo below are sables, the rest seals, just minutes old.
Here, at a day old, you can see a couple sables, as the shimmery silvery gray ones, while the seals will remain dark.
Moms are doing a great job thus far, for both it is their first litter. They made great nests, pulled plenty of fur, and had their babies in the nestbox. Not all new moms have it figured out the very first time.