Kitten toilet behaviour

[Dannieo]

Hi, we recently got 2 kittens and they’re fully litter trained. However in the past few days, we noticed poo in the corner of one of the rooms. We assumed whoever did it wasn’t well. I’ve come down this morning and saw one of them use the litter tray, For a wee but then walked over to that same corner and do a poo! I’ve seen him use the litter tray throughout the day but it seems to be in the morning when it happens.
We even put some tinfoil down in the corner but he still just went at the edge of it!

Any advice would be great. We’ve got them bigger litter trays as we wondered if it was because the kitten ones were too small. It’s just more frustrating because it’s not all the time! Just once a day/once every other day.

[Mollycat]

Some cats don't like using the tray if it already has something in it, or prefer to use one for poo and another for wee. I would put another tray in that corner, you could also try different types of litter.

[Dannieo]

We’ve been really keeping up with cleaning the tray so shouldn’t be a problem really. We can’t put a tray there as it’s Underneath a chair
Considered changing the litter but he’s used that from when he first starting using the litter tray so worried both of them wouldn’t welcome the change.
I’d understand it a bit more if I didn’t see Him use it then move there to do that. We have 3 around the house so he has other options

[Mollycat]

Maybe he would like a covered one?