Mysterious Box

My 11 year old would do this; in fact, he already laid claim to the box my gaming chair came in.

Who in the real world calls a cardboard box a cardbox?

I've tested this out. I was getting a lot of boxes from deliveries, and my cat always knows which box is brand new for her to jump into it and sleep in there for an hour.

I've moved boxes around. I've scattered the stuffing in different places.

She always wants the new box, no matter what.