Our 11 year old cat Smoke is an indoor cat. She has always used her litter box until about 1 1/2 years ago we had to take in her mom Tammy. They did not get along. Tammy would pee on the floor and Smoke would poop on the floor. We decided to put them in a room together to see if they would change there behavior towards one another. We hadn't had any problems for a long period of time. Tammy passed away about 3 months ago. So we bought Smoke a new litter box and let her run free of the house again. About 3 weeks ago she started pooping on the floor again. She will occassionally go in her box, she still goes pee in the box. When she poops on the floor it's always on the carpet and never in the same spot. She only does it at night after we go to bed. If you have any suggestions Please Help! We are lost at this point