Edwin pushes mum in a box

We have kittens at the moment and I think Edwin has been watching Youtube as he decided to shove his mother in a box! This cardboard box has been an endless source of entertainment for the cats and kittens. Soon after removing the contents from the box, I went to dispose of the box in the recycle bin, I went to open out the box in order to squash it flat, only to find kitten Bluebell fast asleep inside it. She so nearly ended up in the bin. Kittens are such fun but they are a worry, I have to do endless head counts.
I have kept the box which is proving to be better than any catnip toy.