New cats and kittens introductions to eachother

Question
Dear Ali,
We have always had several cats in the home, all inside cats.  Three died within the last 1 1/2 years and the young companion to our eldest female passed on in December 2012.  Now we have one male, about 10 years old and the female, about 19.  We adopted a new cat in hopes of it being a companion for the elderly female. This new cat is about 1 1/2 years and very gentle. For the moment, it is staying by its choice in a downstairs room near the room with litter boxes for all cats.  Ahh..the male is refusing to go downstairs to the litter and has used potted plants!  I gave him a temporary box upstairs but he has not used it. He has only seen the new kitty and hisses. I believe once they are acclimated litter will be no problem. But for now, it is a huge problem!

What do we do to get these cats together and how to get the male back to using the normal litter box downstairs?  He seems afraid to venture down there because of the new kitty.  Believe me, he has nothing to fear but he does not know that.  Help!

BTW, I am an expert in Jewelry, Gems and Minerals on this site.

God Bless and Joy. I hope you can make suggestions.  Thomas.

Answer
Thomas,

Typically I suggest isolating a new cat in a small room such as a bathroom for a minimum period of two to three weeks. This gives your resident cats time to get comfortable with the new cat's scent. I suspect that what may be happening with your male kitty opting to use potted plants is that he is upset by the new kitty using the litterboxes. You may need to consider changing the type of litter that you use in order to change the association for your older male... I suspect that moving the new kitty into his own room for a couple of weeks and letting your resident cats get back into their regular routines will help the situation greatly. Once everything has calmed down and the male kitty is back to using his box again you can begin SLOWLY introducing the cats to the new cat's scent by switching bedding between them... This allows the cats to get to know each other in a completely non-confrontational way. Once this is going well you can begin trying treat or meal sessions with the new cat out of his room, but within view of your resident cats... This is going to be a very gradual process, just given the ages of the resident cats involved... Baby steps would be the best way to describe the type of introduction I'm suggesting. If at any point the resident cats begin having issues simply go back to the last step they were comfortable with for a few days to a week then try a half step forward. Patience is key here. If you have any further questions or concerns, please feel free to contact me again at any time - I'm more than happy to help in any way that I can.

Kind regards,

Ali