I've had some great responses to my feline questions before, so now I
am actually writing for my sister and her family.  She previously
owned a spayed female Maine Coon who sprayed everything in sight for
months - furniture, walls, carpet, etc. She did everything they could
to stop it including taking it to the vet, medication, pheromones,
feliway, etc., but it came to the point that she could not have the
cat in her house anymore and had to relinquish it to a new home. (It
is possible that strays outside the house caused the spraying to
begin, as no other causes were determined, but she does have a 12ft
fence around the yard)

It has been about a month, and she has removed the soiled furniture
and carpet in places that the smell could not be rid of, and she has
washed everything as well as she can. She can no longer smell the
odor, but I understand that cats do have better noses than we do.

Her question - She would like to get two female kittens, of any breed.
She is worried that the spraying may begin again if the kittens sense
the spray from her previous Maine Coon. In your opinion, what is the
possibility of this if she spays the kittens before sexual maturity?
Should the kittens be used to the odor by that time, or do you think
the instinct to spray over it and mark the territory as their own will
kick in?

Have any of you dealt with this before?

We'd appreciate your comments,
AMy