Evidently they do:)

Absolutely, both cats and dogs may change color slightly every year they shed

i used to sell a product at cat shows,and i would often listen in on the breeders discussing details about coats and colours and markings....and apparently, there's no such thing as truly black fur....all black cats are really tabbies underneath the black....you can usually see it in the sunlight....i recently had a black cat join my family (and i mean a REALLY black cat....even his toe pads and nose are black), and in the sun i tend to notice a red tinge that appears in stripes.....and since the fur on kittens does often change slightly, it makes sense to me that you're seeing this....

maybe someone has a more scientific explanation.....

Absolutely. Ragdoll cats are born pure white they don't have their full coloring until they are 3 years old.