Hello, I'm hoping for feedback on how to interpret interactions between our resident boy (12 year old rescue) and a newcomer (11 month old rescue).
We have a 12 year old male rescue, who is shy and sweet and has historically loved other cats very much. He was part of an cared for colony until he was about 6 months old. He became exceptionally close to both our other resident cats almost immediately, and stayed that way until they passed away a few years ago. He has been an only furchild for about 4 years.
We recently rescued a young stray, who is estimated by the vet to be about 11 months old. He has been separated from our resident boy for 4.5 weeks, first in a bathroom, and now in a bedroom, while we worked through some health issues, etc. We initially planned to bring him to a rescue organization, but now hope to keep him.
We have been scent swapping, and then site swapping. It was at a point where the kitten purred and cuddled and played with the swapped items; the resident cat sniffed and intentionally sat on the towel from the newcomer's room, etc. They had also seen each other from a distance a few times and seemed interested in each other. Zero signs of aggression. The resident cat would investigate the door separating them occasionally. He would occasionally give a hiss; the newcomer would respond with cute chirping noises and try to play under the door. I was optimistic.
They have recently had their first in person meetings, and I am a little unsure of how they went. I know there are some with lots of experience here, and am hoping for some feedback.
Our resident boy seemed nervous about the newcomer coming downstairs. He watched him cautiously. The newcomer was very interested in the resident boy and approached him multiple times. They touched noses, and the resident cat warned him with a mild hiss (no other signs of aggression). The newcomer explored around the house, played randomly, but kept coming back to see the resident boy, wanting to be close to him, purring, sometimes meowing, and even making biscuits on the couch next to him. However, his tail was puffed at times. His ears seemed relaxed and normal, he did not stiffen, did not seem like he was about to attack. No hissing from him at all; just purring, biscuits, keen interest, and puffiness.
At one point, when he was close to the resident boy, the newcomer kind of reached out to him - I do not think it was a swat, it did not seem aggressive - but I am not sure what his intention was. I ended that meet and greet and brought the newcomer back upstairs to his room.
Today, during a separate interaction, the newcomer was close to the resident boy and sniffing him. The resident boy was tolerating this cautiously. The newcomer meowed occasionally, purred, etc - then randomly seemed to actually nip at or bite the resident cat! It sounds strange to say but it did not seem aggressive - he was purring, etc. No marks or blood or anything. No fight ensued. I redirected then put the newcomer back in his room. The resident boy obviously didn't love that interaction but did not run away and hide after (I would normally expect him to do that if he was scared).
after this interaction, I scent swapped again, and the. newcomer immediately went on the blanket from the resident cat's area, smelled it, then starting making biscuits and purring.
I'm trying to interpret these interactions to figure out if the newcomer is being aggressive. It's so strange with the purring and biscuits, combined with the puffiness, etc.
Any advice would be appreciated. Does it sound like the new boy was being aggressive? It was such a strange interaction (to my untrained eyes, anyway!).
I am leaning toward returning to strictly scent and site swapping for now.
We have a 12 year old male rescue, who is shy and sweet and has historically loved other cats very much. He was part of an cared for colony until he was about 6 months old. He became exceptionally close to both our other resident cats almost immediately, and stayed that way until they passed away a few years ago. He has been an only furchild for about 4 years.
We recently rescued a young stray, who is estimated by the vet to be about 11 months old. He has been separated from our resident boy for 4.5 weeks, first in a bathroom, and now in a bedroom, while we worked through some health issues, etc. We initially planned to bring him to a rescue organization, but now hope to keep him.
We have been scent swapping, and then site swapping. It was at a point where the kitten purred and cuddled and played with the swapped items; the resident cat sniffed and intentionally sat on the towel from the newcomer's room, etc. They had also seen each other from a distance a few times and seemed interested in each other. Zero signs of aggression. The resident cat would investigate the door separating them occasionally. He would occasionally give a hiss; the newcomer would respond with cute chirping noises and try to play under the door. I was optimistic.
They have recently had their first in person meetings, and I am a little unsure of how they went. I know there are some with lots of experience here, and am hoping for some feedback.
Our resident boy seemed nervous about the newcomer coming downstairs. He watched him cautiously. The newcomer was very interested in the resident boy and approached him multiple times. They touched noses, and the resident cat warned him with a mild hiss (no other signs of aggression). The newcomer explored around the house, played randomly, but kept coming back to see the resident boy, wanting to be close to him, purring, sometimes meowing, and even making biscuits on the couch next to him. However, his tail was puffed at times. His ears seemed relaxed and normal, he did not stiffen, did not seem like he was about to attack. No hissing from him at all; just purring, biscuits, keen interest, and puffiness.
At one point, when he was close to the resident boy, the newcomer kind of reached out to him - I do not think it was a swat, it did not seem aggressive - but I am not sure what his intention was. I ended that meet and greet and brought the newcomer back upstairs to his room.
Today, during a separate interaction, the newcomer was close to the resident boy and sniffing him. The resident boy was tolerating this cautiously. The newcomer meowed occasionally, purred, etc - then randomly seemed to actually nip at or bite the resident cat! It sounds strange to say but it did not seem aggressive - he was purring, etc. No marks or blood or anything. No fight ensued. I redirected then put the newcomer back in his room. The resident boy obviously didn't love that interaction but did not run away and hide after (I would normally expect him to do that if he was scared).
after this interaction, I scent swapped again, and the. newcomer immediately went on the blanket from the resident cat's area, smelled it, then starting making biscuits and purring.
I'm trying to interpret these interactions to figure out if the newcomer is being aggressive. It's so strange with the purring and biscuits, combined with the puffiness, etc.
Any advice would be appreciated. Does it sound like the new boy was being aggressive? It was such a strange interaction (to my untrained eyes, anyway!).
I am leaning toward returning to strictly scent and site swapping for now.
I think you may be right and will keep letting them interact, just keeping a close eye on them for now. 
I put the newcomer back in his room at that point. They are still separated most of the time. I give them time together, but it is closely supervised. It has to be, because every time my poor resident guy even tries to stand up, the newcomer's focus zeroes in on him with considerable intensity and he visibly itches to chase him and jump on him. My resident boy is a senior, overweight, with multiple health issues. He is shy and quite meek (he has taught no manners at all in response to the newcomer's biting, for example). I can't imagine putting him through this long term.
