(2) 5 month old kittens

Question
Hello!...So, I got my 2 kittens when they were 6 weeks old....the boy
is a manx and the girl is a hemingway, they are brother and sister.. my
little anomoly's.lol..anyway..they loved each other until Thursday,
when I took the little boy in to get altered..since he has come home my
little girl has hissed at him and the GROWLING is insane, yesterday was
the first day that she has sort of calmed down, but this morning world
war 3 has started all over again..it is all her, he wants to play with
her and she is awful to him!!!!what is happening to them? I'm taking
her this Tuesday to get altered as well, will it calm down? and since
Thursday the peeing has gone beyond all limits I have.. my boy altered
kitten will be laying on the couch and will just pee it is almost
like.. in his sleep he does it? and they have started peeing on my bed?
(AHHHHHHHHH!!!!) I have two kitty litter boxes on oppisite ends of the
house for them and one is an auto kitty litter box...can you please
help me with these questions of there behavior?

Thank you!!!!
Kelley  

Answer
Hi Kelley.  I would definitely separate them for now.  The stress of all the strange smells your male carried home is too much for your female.  Keeping them together now is only going to worsen things.  I'd give them 5-7 days apart for everything to calm down, and then reintroduce them slowly.  You shouldn't have a problem at that point.  

As far as urinating outside the box, I would definitely call the vet on that one.  Neutering rarely causes continence problems, but if something didn't go according to plan, it is possible.  I wouldn't hesitate to call the vet at all.

Another reason may be that he's too afraid of his sister right now to get near the litter boxes.  If that's the case, once you separate them, he should use his box.