After one month
The little grey cat is still hiding under my sofa, scared of his new home.  The big orange cat is new here too but likes the place and walks freely through every room.  He’s seen Grey but doesn’t go under the sofa to meet him; he's content to rule the apartment alone.

After two months
Grey came out from under the sofa for the first time.  I was eating breakfast.  Grey walked slowly up to Orange and they touched noses.  Grey flinched at every sound in the room and soon scampered back under the sofa, his white paws flashing.  Orange didn’t care. 

After three months
Grey wants to get to know Orange.  Orange wants to be left alone.  When Grey gets within six inches of Orange a fight breaks out with ugly snarling noises, but when I break it up there’s no harm done.  And after a minute Grey goes right back to sniff Orange’s face.  Orange stands still now.  It looks like Grey saying “Are you OK?”

After six months
Orange is sleeping on my lap as he has from day one.  Grey walks in the room; Orange sees this and gets up, hops down, and leaves the room.  Grey hops onto my lap, curls up and falls asleep.  This happens every week now. 

Whenever I get home from work, little Grey greets me at the door and Orange hangs back, not wanting to come near Grey.

After one year
Every night, Orange sleeps at the foot of my bed.  Grey had been sleeping in the living room.  One night at bedtime Grey tried to hop onto the bed with Orange and a horrible fight broke out.  Orange will continue to defend the bed as his territory.  

After one year, six months
I work a half day, getting home at 1:00 pm, a rare thing. No cats greet me at the door.  I go into the bedroom and find Orange and Grey sleeping on the bed, two furry circles just a foot apart.  They look up at me frowning.  They put their heads down, one after the other, to sleep again.

After two years
Grey walks up to Orange every day at some point.  Grey bows his head and Orange forcefully licks the top and back of Grey’s head for ten seconds.  Grey walks away, no fuss.