Our kittens are nearly 8 weeks old. They were birthed in a cleaned out igloo style litter box and spent their first few weeks there. When they got to 4 or so weeks, the guy who owned the mother half filled the litter tray with litter, so they would learn to go. They were still sleeping in there at the time. (Yes I know) We've had them a week now. They are absolutely excellent at using the tray and we have had no accidents at all. However, they seem to think it's a playpen. They playfight in there, roll about, and I've even caught them playing with clumps of litter (World's Best so kitten safe clumping). The tray is in a quiet part of our home (in the bathroom) so completely away from their bed, food and toys, yet they still enjoy a play in there, I assume because they got used to it in their first home. It means that, unless I am extremely quick on the uptake, I'm having to clean kittie poo out of fur and paws as, while one goes to the toilet, the other prepares to pounce! I'm loathe to remove them from the tray unless they are obviously just playing, because they are still so young and at that stage where any use of the tray is accompanied by lots of digging and fuss, and I would hate to accidentally remove them if they were preparing to go. Obviously I cannot restrict access to the tray, so my question is - is this normal? I've only had fully grown rescue cats before, and they've all been in and out the tray as quick as possible. Is there anything I should do, or is it just a phase they will outgrow? I'm not bothered about it really - I'm not phased by kitten poo, but just concerned it's not good for them. They are fully wormed etc.