Cat Fight??

Question
I'll try to explain my cat issue as short as possible.  My Female Cat Spookums who have been with me for over a year, has lost her sister a while back.  My husband decided to adopt 2 more kittens (female/Cimeron & male/Jax) to keep her company since she lost her sister.  It took us a while before we could have them all play together and they did thank God, though it took time before they started to stop hissing each other.  They were able to sleep and play together for quite some time now, however today was not a good day.  Our old Cat Spookums suddenly was hissing at my male cat Jax for some reason.  It was a fight I have never seen before.  It was indeed a bad fight I must say.  Jax, our new male cat seemed to have hurt Spookums in some way.  As of this time, I have hid them away from each other to cool off.  My other new female cat Cimeron seems to be fine though.  I haven't seen her fight any one yet.

Please help...Will this be a problem for me having a male and female cat (who are not related?) Or is this just a phase.  I will need to hear from you soon as I need to know what to do as of this time, whether or not to keep them separately for now or continue for them to stay together?  

Thanks,
Ann Marie

Answer
Obviously something unusual happened. I think its best you keep them separate a little and introduce them slowly again perhaps as you did in the beginning when they were new together. they will have to re-accept each other. I really can't tell you what will happen or when becasue we can't tell why it happened. Its just possible she is getting older and didn't want to be bothered with the younger ones play. It could have easily been a one time event. I don't think the two unrelated of differing gender is a biggie but you don't say if they are spayed and neutered. Now if he's not neutered and she's not spayed then he may have attempted to mate and she told him where to go on that idea - or, it actually happened and she wasn't too happy about it. Then you have a new problem of potential kittens. So if they aren't fixed, I'd check it she's preganant, and if she is, I would have it aborted cery early and her spayed asap. And him fised and your other girl spayed too. If they all were already fixed or the kittens are too young still, then i would just take it as a one time fluke for now and slowly reintroduce them in supervised play over time until things become normal again.