I keep my cats in small groups, boys and girls are kept separate except for this time of year when the girls most definately aren't calling, then I put three girls and two boys (ones a neuter) all together and they all get on really well. I have three girls indoors all the time and if one goes out for the day the other two don't eat until the wanderer returns. I wish I could have them all indoors, as they are all such good company, but they'd wreck the joint, we had 18 coonies at one time in a cottage... it didn't work out that well for the house!