New Cat

We've nick named the new cat 'the kitten' as it's a bit smaller than our little fat beast Mauzer. There has been 2 sightings recently, and both times our cats go in for a sniff/kiss, then seem unsure if to be friendly or fighty. It was a triangle of cats all sat watching each other, then was a kerfuffle with a little mouse-y creature which the kitten ran off with.