I have a similar problem with my newer kitty - who was an only cat until I adopted her, then became the youngest of 3 (2 sr citizens and her). My house is really small, so I don't know where I'd put another litter box.

But thank you for the reminder to spend some quality time with the younger cat - who is the one I'm having litter box problems with. I suppose in her eyes, me medicating the other two twice daily is me "spending time" with them. Need to make a point to get new batteries for the laser pointer - she likes to play with that.