He's been here for two days in his own room. My other cat is pretty pissed about his coming and hisses at the door, although her behavior is improving. They have not seen each other yet as expert advice and reading up on this subject has instructed. My question is, I'm taking Benvolio (new kitten) to the vet tomorrow...do you think I should leave his door open when we leave so Dot (older cat) can smell around? Or, is it too soon? She seems to be coming around slowly, and I don't want to set her back by overwhelming her with another cats scent, especially because no one will be home to monitor her. But, it also might be good for her to become more familiar with Benvolio's scent. Any advice?