I'm hoping for some advice
We have a 15 month old resident cat - she's big; about 6kg.
We bought home her little brother 10 days ago - he's 15 weeks old, about 1.5kg.
It's gone from hissing and growling to sleeping together and mutual grooming fairly quickly, but there's a lot of rough play. No fur flying, no blood! Sometimes, however, growling from the little one. I'd say it definitely starts as play, and they both instigate fighting at different times. But I do break them up if he growls or squeaks because she is just so big and it scares me when she kicks him with her back legs.
We've been keeping him in a kitten pen at night, she sleeps in the same room, and then having them out together whenever we're home.
We're away for two nights over Christmas, I have family who will be checking in on them.
Do I leave him cooped up, but safe, in the kitten pen the whole time, or do I let them both stay out and risk over-rough play without me there to stop it?!