Did you find the fourth cat in this morning’s picture?
I’m not absolutely sure about this. But I’ve circled what looks like a tail, and some people say in the original post that the other part of this cat (the head) is behind the top right cat. At any rate, the top left cat cannot have two tails, and that orange bit I’ve circled is stippled like a tabby, and is not similar to the orange bits in the rest of the cover.
I may of course be wrong, but this is my best guess. And of course there might be only three cats. The camouflage is clever, of course.

Could be. Does anyone know for sure? I can’t deal with such uncertainty. (Just kidding, of course.)
I saw that, and although the markings are fairly persuasive, it looks too wide to be a cat’s tail. I’m going with the fourth (or fifth?) cat being the one that’s peering out from behind the curtain at the upper-right, with the right eye and a backturned ear visible.
I think you found it! The ear is clear once you pointed it out.
I think to the left of the bottom cat. (Behind its rump.) That color is of a calico cat, not the pure colors of the blanket. Maybe it’s behind/under that cat?
My conclusion too.
In this Reddit thread on the same picture, the OP keeps telling people their guesses are wrong, but doesn’t ever reveal the answer.
https://www.reddit.com/r/FindTheSniper/comments/1mf07tx/find_the_fourth_cat/
The fourth cat is the one that’s barely peeking out from behind the curtain!
That’s per the Reddit thread you linked to. The solution probably wasn’t posted until after you checked.
I thought it was reflected in the lower right pane of the cabinet. Need a higher resolution image.
I thought it was the little bit sticking out behind the rear-most cat, occluding the small part of the glass cabinet.
I thought it was on the container in the cupboard at the very top!
I think I see a tiny white cat peering out from behind the glass of the cabinet in the background.. on the top shelf far right..from inside. Somebody better let him out. Maybe I need more coffee
I think you are in the right area, the cat nearest the circle is 2 cats, one facing the camera and the other facing directly to the right, you can’t see it’s head. I think the body of the facing cat looks weird otherwise.
Hocus pocus going on there.
There is no fourth cat I tells youse all! Unless it’s underneath the cat at top right.
The topmost cat has in its fur (right in the middle) the head of a kitten. That is the only part of the kitten though…