Hi what I do is I use a giant crate and when the kittens are 4weeks old I start putting the litter tray in with mum & them so they watch her use it, I start putting them in and digging their paws in to and I shut them in the crate over night for a week, (the day time they have the entire room) I always make sure that it has some of mums wee scent in it to for them to smell, never had any accidents after Ive been doing this, only had 2 accidents in my first litter then since Iv done this Ive had none, they are now 6 weeks and we are confident enough to let them round the house & they now use over litter trays available without me telling them

Hope this helps!

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Steph

aka The NO! ->

Thank´s for these advices

I think you are right that the space is too large for them. I will try to put them in smaller space this night because major of the accidents happen at night.
Although i will probably not be able to sleep all night because kittens mum will scream her head off if she cant get to her babys