I had my cats litterbox in the bathroom and my one 7 month old kitten Peaches would follow me in there when I had to go and would either use the litter box at the same time or would sit and watch me, a couple of days ago he was in there with me and used the litter box and then after he was done he pulled down some of the toilet paper and rubbed his backside against it like they do when they are rubbing against your legs, it looked like he was trying to wipe himself like he see's me do, the next day my parents were over and they suggested I put the litter box behind the bathroom door out of the way so I moved it and when he followed me in there the next time I used it he looked around like "where is my potty" and just for fun I told him "the litter box is behind the door" and he actually walked out and looked behind the door.