I have two kittens. One is about 3 months and has had all of her shots (due for a booster this week). I just rescued a 3 week old kitten who came from a litter that probably has URIs but he looked the healthiest. He's kept in a box in our room, and that's the room the old kitten stays in too...
I have a girl "kitten" of about 3-4 months old. She has grown so much since we rescued her at 3 weeks old. We just reached another kitten, a male of 5 weeks old. Our girl HATES him. We messed up and let her get sight of him when we brought him home (we should have hid him) and she went crazy...