When I first got Lucky he was really tiny, about the size of an adult mouse, so we put him in a temporary aquarium. I had to use an aquarium because he was so small he could fit right between the bars of all the wire cages I had. I eventually wanted to put him in the big cage with my 4 other rats so he wasn't alone.
Lucky is getting bigger and is more trusting and loves to come out and play now. When I first got him, he ran from my hand..now I put my hand in his cage and he jumps on waiting to be picked up.
We introduced Lucky to Bandit while they were on the couch together and the introductions went quite well. They smelled each other, licked each other and chased each other around. Lucky is still too small to go in the big cage but I figure it will be very soon that he can join his cousins.
We'll be making more introductions with the other three boys slowly as he gets bigger, but the first one went quite well. I'm very happy.