Mags won't get along with new cat

This is a place to gain some understanding of cat behavior and to assist people in training their cats and dealing with common behavior problems, regardless of the method(s) used. Keep in mind that you may be receiving advice from other cat owners and lovers...not professionals. If you have a major problem, always seek the advice of a trainer or behaviorist!


Purred: Thu Oct 3, '13 1:17pm PST 
Okay, I got a new cat, Galileo, a little over a month ago. At first Mags, the only resident cat before Leo, hid and wouldn't come out of my bedroom, then she swatted him every time he looked at her. Things have gotten better but she still swats, hisses, and growls (though not as often as before and she can pass a couple inches from him without much care). There hasn't been any serious fights but Leo has gotten a couple of scratches (not serious or recent). It's just Mags that is the problem, Leo is very friendly and tries to play with her a lot even, only twice have I seen him actually being aggressive. When Mags is in a good mood and not acting out towards Galileo, she's pretty tolerable, letting him sleep in the same bed a couple feet away, letting him sit in a window seal with her on occasion, even if the situation is right, letting him lay up against her (as long as he doesn't move and preferably facing away from her), and when this happens she'll even start licking him a bit (body parts away from his head). I have all of their stuff separated, three litter boxes (there were two before and they were starting to get territorial around them so I got a third one which seems to have solved the problem), two food bowls, three water dishes, and two scratching pads. Most of which is in my room since both of them spend most of their time in there.
Should I just give them time and see if they work it out or should I try something else? (reintroduction is out of the cards right now, don't have a spare bedroom to put Leo in.)
I see a lot of suggestions for Feliway on here, and it looks good and I would get it if it wasn't so expensive. I will though if its my last option.
And I might add that Mags is about 2 1/2 and Leo is almost 10 months now. Will the situation improve when he gets older and calmer?
Also more recently Mags has been biting Galileo's butt, like aiming for his male parts (though he is fixed). No bites from Mags have ever drawn blood, but they do seem aggressive. Is this a sign of dominance or something?
Sorry if this all seems a bit jumbled, I'm just a little stressed and freaked out; I tend to panic over every little thing. I do try to keep a good humor about the cats though, so that they don't get stress from my stress.