I have only owned male cats and from my experience and other people's posts about female cats,they seem to tolerate a multi-cat household better. I just recently adopted a new almost 9 month old cat named Cirrus. It only took Storm about 4-5 days to accept him but my other cat Sunny is still having some issues. I've only had Cirrus for 9 days so it's still very early and I'm sure Sunny will accept him soon. When my RB Pepper was still alive, all 3 of my cats got along very well. I guess it all depends on the cats personality. Good luck.