Cat peeing on floor after other cat died

Question

My babies   I have a 6 year old tabby (my Crazy) who has always been my baby. She's very attached to me (greets me at the door when I get home every day, sleeps under the covers with me, etc). Until last week, I also had a 16 year old kitty (Skunky) who lived with me and Crazy for the past five years. Last week, we had to put Skunky to sleep (high blood pressure had caused her to go blind, make breathing almost impossible to the point that she was breathing with her mouth open, and in the last month or so she stopped using the litter box- I cleaned the areas she was using well and began to carry her to the litter box two or three times a day, and the outside box usage stopped).

We had to put Skunky to sleep on Tuesday 2/5. By scheduling chance, I was off work that entire week. Crazy cat barely left my side. She and Skunky were never very close: they certainly didn't cuddle or play together, but Crazy would occasionally groom Skunk. Crazy tried to play with Skunk, but Skunky would have nothing to do with it (so she'd hiss and run off). Both cats slept in the bed with me, most of the time. (Crazy always, Skunky about 70% of the time)

After being back at work for a week, I've noticed that Crazy hasn't peed in the box. The first couple days I scooped the box, there was a little bit of pee, so I didn't even notice it. Then I went two days between scooping and realized she hadn't peed in the litter box at ALL. She is still pooping in the box, but I believe she started peeing behind the couch, where Skunky peed in her last few weeks.

I thought I had cleaned the area well enough and Crazy has NEVER peed outside the litter box in her life.

Is Crazy simply upset/grieving and peeing where Skunk did because she misses her sister? Could she be lonely during the day while I am at work and spending time where Skuny did, and as a result peeing there because some smell remained afterall?

I'm at a loss. Any tips or answers you have would be greatly appreciated! I love my Crazy cat and want to make sure she's alright.

Answer
Kate,

I am sorry for your loss of Skunky!!!!!!!!!!

As for Crazy, she is going through some separation anxiety over the loss of Skunky.  The are where Skunky pee'ed needs to be cleaned thoroughly with an enzyme based product made especially for pet stains and pet odors. You might consider getting a product called Magic-Zymes Plus and follow the directions to clean the area thoroughly (See: http://www.magic-zymes.com/).

After you clean it, you may want to tape down aluminum foil over the area as aluminum foil often discourages them from peeing in the area. In addition, I would get some Dr. Elsey's Cat Attract litter additive to add to the existing litter which may help Crazy remember where she should pee!!!!!!

It usually takes a couple of weeks for a cat to get over grieving for a lost buddy.

Please let me know how things develop.

Sad regards... Norm.