Cat poop at our front door

We went on vacation for 2.5 weeks. We had a pet sitter who was SUPPOSED to come in every other day for the first 1.5 weeks and every day for the last week. I don't know if she did or not.

However, when we got home about a week ago we were greeted to some poop in our foyer. She left a note saying one of the cats was not pooping in the litter box. I figured maybe she didn't empty the litter box on time and a cat didn't want to use it.

However, it has happened twice in the past week. It happened last night between 12am and 5am. I had just emptied the litter box yesterday afternoon. The foyer is a hardwood floor, there is no way to bury it there. The cat just pooped there and left.

I don't know which cat it is. I have a feeling it is the larger male (that is what our pet sitter thought in her note as well) just because he is the 'odd' one. He is very skittish and he is also very messy with the litter box (pees on the side, kicks litter everywhere if it's not covered, etc.). He has some qualities which make me think he was either abused or a stray at one point in his life. I tried looking at the 'deposit' up close (not pleasant!) but I couldn't see any fur in it which would indicate which cat it came from.

What makes this more odd is the cats are NEVER in the foyer. You have to go down some stairs and the foyer is basically a 5x5 foot space. The cats just don't spend time down there. Period.

What could possibly be causing this behavior? I haven't changed out the litter in 3 weeks. Could that cause it? Or could it be something else? Is there any way we can find out which cat is doing it?

Either the cat did not like it when you went on vacation and/or he needs to see a vet, he may be having problems.

He is probably getting back at you for leaving! (If the vet rules out any problems)

He'll probably quit doing this after he settles down a bit. Cats really hate change.

Before we take a cat to the vet we have to know which cat is doing it. Any suggestions?

Cats can mark their territory with poop the same as urine. They will leave a poop uncovered in the box so other cats know it is theirs.

It sounds like your cat was aware you were away and was not thrilled with the sitter, and left a poop at the point of entrance where the sitter was coming in to mark territory.

Now the sitter is gone but the poop place has become habit.

Or, your kitty is still a bit stressed, and pooping there makes him feel secure because he is giving structure to his territory. And when you were away, that structure and territory felt threatened.

I would give him lots of structure and reassurance now that you are back, and also really scrub the area where he was pooping (use an enzymatic cleaner and cover it with sheets of loose aluminum foil. And/or maybe put a litter box there for a little bit and gradually move it to the place where his normal box is.

As far as which cat it is, I would watch the existing litter box, especially when you get home at night and they wake up and get moving, which is when kitties normally go (just like people). I would see who is covering their poop and I would get up and follow them if I saw them going for the foyer.